978 resultados para hair coat, sheath, navel


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This paper is a joined publication of the Depts. of Genetics and of Technology, of the E. S. A. "Luiz de Queiroz", Universidade de São Paulo, and deals with the variation of the percentage oil content in the whole seeds, the embryos and the seed-coat of 28 varieties of castor-beans (Ricinus communis, L.). Primarily, the authors, as a justification of this paper, make reference to the applications which castor-oil has in industry, medicine, etc. In accordance with the weight of 100 seeds, the varieties of castor-beans were classified into 3 classes : small seeds (100 seeds less than 30 g), medium seeds (100 seeds between 30 g and 60) and large seeds (100 seeds more than 60 g). The percentage of oil in the seed, embryo and seed-coat, the dimensions of the seeds and the weight of 100 seeds are given for every variety in table 1. In order to obtain an estimate of the variability for the methods of determination of the oil percentage, in the 3 differents parts of the seeds and also in the 3 groups of seeds, the coefficient of variability was calculate (table 2). It is showed that the variation in the seed and embryo is low and that in the seed-coat is very high. The analysis of variance, with regard to the difference among the 3 types of seeds (small, medium and large), among the 3 parts of the seed (whole seed, embryo and seed-coat) and residual error, is given in table 3. Only, the oil content of whole seeds among types of seeds was significant at the 5% level. The t test among the correspondent means is not significant for the difference between medium and large seeds is significant between both these types (medium and large) and small seeds. The fiducial limits in relation to the mean of the oil percentage in the 3 differents types of seed, show that there is one variety (n. 1013-2), which has a percentage of oil, in the medium type of seed, significantly at the 5% level (table 4), higher than the general mean. Since the distribution of the percentage of oil in the seedcoat is discontinuous, 5 groups were established (table 5). All the differences between groups are significant (table 6). For practical purposes, when we have to remove the seed coat, one should eliminate those varieties which loose at least 3% of oil by this procedure. There is a significant linear correlation at 5% level between the percentage of oil in the seed and in the embryo, of the smali and medium type of seeds (table 7), and also, when taking the 3 types together (lower part of table 7), one finds that the same is true. Also, the correlation between the percentages of oil in the embryo and in the seed-coat of the 3 types together is significant at 5% level. According to the results obtained in relation to the percentage in 28 varieties studied, it can be recommended, for breeding purposes, to work only with those varieties which belong to the medium and the large types of seeds.

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The author has studied the domatia appearing in the Rubiaceae family by examining 622 species distributed among 113 genera; and has verified that 88 species belonging to 35 genera have domatia fitting in the "touffe de poils", "en pertuis" and "em pochette" types according to the Chevalier's Classification. 39 species present domatia that display chamber, duct and outlet orifice. The other 46 species present domatia either as hair-agglomerates, hair-clusters or scattered hairs. The domatia in Paveta indica L. and Vangueria edulis Vahl. are in the shape of a little holow in the blade tissue and have no hairs. In Borreria verbenoides Cham & Schl. the domatia are formed by an elevation in the limb and presents abundant and short hairs. In Bqthryopora corymbosa Hook f. and Gardenia Thumbergii L. the domatia appear also in the nervure axils of several orders and also in Rudgea lanceolata Benth., Rudgea subsessilis Benth. and Rudgea gardenoides Muell. Arg. are they located7 in the axilla of the angle directed toward the leaf base.

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The author has studied the domatia appearing in the Rubiaceae family by examining 278 species distributed among 95 genera; and she has verified that 51 species belonging to 29 genera have domatia fitting following types according to the Chevalier's classification: in the "touffe de poils", "em pertuis" and " enpochette". Fourtheen species showed domatia that has chamber and outlet orifice. The others 29 species present domatia either as aglomerates-hair, clusters-hair or scattered hairs and variations of this types; eight species present domatia "em pochette". On Paurichiantha rubra (Benth.) Brem., Rondelettia purdiei Hook f., and Randia cladantha K. Schum the domatia also appear in the axils nervure of several orders; and also in Psychotria racemosa Aubl., they are located in the axil of the angle toward the leaf base. The author observed for the first time two types of domatia in the same leaf on Psychotria fortuita Standi, and on type of domatia, with hairs, that is formed by a fold on the blade on Chomelia tenuiflora Benth.

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According to E. Chagas (1938), South-American Kala Azar is a widespread disease from the jungle, several cases being reported from North Brazil (Estado do Pará: Marajó Island, Tocantins and Gurupi river valleys; Estados do Piauí and Ceará: coast and hinterland). Other cases were found in Northeast Brazil (Estados de Pernambuco, Alagôas and Sergipe: coast and hinterland; Estado da Bahia: hinterland). A few cases were described from Estado de Mato-Grosso (Brazil), Provincia de Salta and Território do Chaco (Argentine), and Zona contestada do Chaco (Paraguai-Bolívia). A well defined secondary anemia associated with enlargement of the liver and spleen are the chief symptoms. Death usually occurs in cachexia and with symptoms of heart failure. Half the patients were children aged less than ten years (CHAGAS, CASTRO & FERREIRA, 1937). Quite exhaustive epidemiological researches performed by CHAGAS, FERREIRA, DEANE, DEANE & GUIMARÃES (1938) in Municipio de Abaeté (Estado do Pará, Brazil) gave the incidence of 1.48% for the natural infection in human, 4.49% in dogs, and 2.63% in cats. The infection was arcribed (CUNHA & CHAGAS, 1937) to a new species of Leishmania (L. chagasi). Latter CUNHA (1938) state, that it is identical to L. infantum. ADLER (1940) found that so far it has been impossible to distinguish L. chagasi from L. infantum by any laboratory test but a final judgment must be reserved until further experiments with different species of sandflies have been carried out. Skin changes in canine Kala Azar were signaled by many workers, and their importance as regards the transmission of the disease is recognized by some of them (ADLER & THEODOR, 1931, 2. CUNHA, 1933). Cutaneous ulcers in naturally infected dogs are referred by CRITIEN (1911) in Malta, by CHODUKIN & SCHEVTSCHENKO (1928) in Taschkent, by DONATIEN & LESTOCQUARD (1929) and by LESTOCQUARD & PARROT (1929) in Algeria, and by BLANC & CAMINOPETROS (1931) in Greece. Depilation is signaled by YAKIMOFF & KOHL-YAKIMOFF (1911) in Tunis, by YAKIMOFF (1915) in Turkestan. Eczematous areas or a condition described as "eczema furfurace" is sometimes noted in the areas of depilation (DONATIEN & LESTOCQUARD). The skin changes noticed by ADLER & THEODOR (1932) in dogs naturally infected with Mediterranean Kala Azar can be briefly summarized as a selective infiltration of macrophages around hair follicles including the sebaceous glands and the presence of infected macrophages in normal dermis. The latter phenomenon in the complete absence of secondary infiltration of round cells and plasma cells is the most striking characteristic of canine Kala Azar and differentiates it from L. tropica. In the more advanced stages the dermis is more cellular than that of normal dogs and may even contain a few small dense areas of infiltration with macrophages and some round cells and polymorphs. The external changes, i. e., seborrhea and depilation are roughly proportional to the number of affected hair follicles. In dogs experimentally infected with South-American Kala Azar the parasites were regularly found in blocks of skin removed from the living animal every fortnight (CUNHA, 1938). The changes noticed by CUNHA, besides the presence of Leishmania, were perivascular and diffuse infiltration of the cutis with mononuclears sometimes more marked near hair follicles, as well as depilation, seborrhea and ulceration. The parasites were first discovered and very numerous in the paws. Our material was obtained from dogs experimentally infected by Dr. A. MARQUES DA CUNHA< and they were the subject of a previous paper by CUNHA (1938). In this study, however, several animals were discarded as it was found that they did develop a superimposed infection by Demodex canis. This paper deals with the changes found in 88 blocks of skin removed from five dogs, two infected with two different canine strains, and three with two distinct human strains of South-American Kala Azar. CUNHA'S valuable material affords serial observations of the cutaneous changes in Kala Azar as most of the blocks of skin were taken every fortnight. The following conclusions were drawn after a careful microscopic study. (1) Skin changes directly induced in the dog by the parasites of South-American Kala Azar may b described as an infiltration of the corium (pars papillaris and upper portion of the reticular layer) by histocytes. Parasites are scanty, at first, latter becoming very numerous in the cytoplasm of such cells. Sometimes the histocytes either embedding or not leishman bodies appear as distinct nodes of infiltration or cell aggregations (histocytic granuloma, Figs. 8 and 22) having a perivascular distribution. The capillary loops in the papillae, the vessels of the sweat glands, the subpapillary plexus, the vertical twigs connecting the superficial and deep plexuses are the ordinary seats of the histocytic Kala Azar granulomata. (2) Some of the cutaneous changes are transient, and show spontaneous tendency to heal. A gradual transformation of the histocytes either containing or not leishman bodies into fixed connective tissue cells or fibroblasts occut and accounts for the natural regression just mentioned. Figs. 3, 5, 18, 19 and 20 are good illustrations of such fibroblastic transformation of the histocytic Kala Azar granulomata. (3) Skin changes induced by the causative organism of South-American Kala Azar are neither uniform nor simultaneous. The same stage may be found in the same dog in different periods of the disease, and not the same changes take place when pieces from several regions are examined in the same moment. The fibroblastic transformation of the histocytic granulomata marking the beginning of the process of repair, e. g., was recognised in dog C, in the 196th as well as in the 213rd (Fig. 18) and 231st (Fig. 19) days after the inoculation. (4) The connective tissue of the skin in dogs experimentally infected with South-American Kala Azar is overflowed by blood cells (monocytes and lymphocytes) besides the proliferation in situ of undifferentiated mesenchymal cells. A marked increase in the number of cells specially the "ruhende Wanderzellen" (Figs. 4 and 15) is noticed even during the first weeks after inoculation (prodomal stage) when no leishman bodies are yet found in the skin. Latter a massive infiltration by amoeboid wandering cells similar to typical blood monocytes (Fig. 21) associated to a small number of lymphocytes and plasma cells (Figs. 9, 17, 21, and 24) indicates that the emigration of blood cells...

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The A. and his co-workers captured in trips in the hinterland of Brazil more tham 17.000 flebotomi from which 35 are new ones, 11 discribed by, him in previous papers. The A. found these insects in groups of species living in different habitats, some ones of them not yet known: ondoors, or outdoors attracted by light or animal baits, without Shannon’s trap, in great or small caves, in the jungle in tree’s holes, holes in stones, holes in the soil habited by animals like armadillos, pacas (Aguti paca), wild rats, cururú toad (Bufo sp.). He observed the life history of 13 species: Flebotomus longipalpis Lutz& Neiva, 1912, Flebotomus intermedius Lutz & Neiva, 1912, Flebotomus avellari Costa Lima, 1932, Flebotomus aragãoi costa Lima, 1932, Flebotomus lutzianus Costa Lima, 1932, Flebotomus limai fonseca, 1935, Flebotomus rickardi Costa Lima, 1936, Flebotomus dasipodogeton Castro, 1939, Flebotomus oswaldoi n. sp., Flebotomus villelai n. sp., Flebotomus triacanthus n. sp., Flebotomus longispinus n. sp. And flebotomus travassosi n. sp. He describes the male of 24 n. sp., explaining the differential diagnose of group or nearly allied species. He inclued F. rooti n. sp. And F. hirsutus n. sp. In the sub-genus Shannonomyia. The first one, very allied to F. davisi Root is different from it, for presenting in the dorsal side of the abdomen bristles and not scales and to have the median claspers longer than his inner appendage and F. hirsutus quite different from the others which show 3 spines on distal segment of the upper clasper and for being the only one who presents the bristles of inner appendage of median clasper longer than it. Only the females of F. amazonensis Root and f. chagasi Costa Lima, are known and then it is possible that they belong to one of the species of this sub-genus from whom only the male have been described. F. choti Floch & Abonnenc, captured also at Pará, F. triacanthus n. sp. F. trispinosus n. sp. And F. equatorialis n. sp. Are very related and to this group the A. proposes the same of Pressatia as sub-genus in honor to whom demonstrated the medical importance of the flebotomi, considering F. triacanthus as the type specie of this sub-genus. In this sub-genus the V papal joint is very long, longer than III + IV, the antennae with geniculated spines without posterior outgrowth. At the genitalia the basal segment of the upper clasper presents two types of bristles ou the inner face, arranged in tuft; the distal segment with 3 spines and 2 thin bristles something difficult to see one of them situated near the apical spine and the other on the base of tubercle where the median spine is articulated; the median clasper is unarmed and compressed; the inferior clasper is also unarmed and longer than de basal segment of the upper clasper; the pompeta is longer than the basal segment of the upper clasper. Following it is presented a key for the determination of the males of the four species of this sub-genus. F. micropygus n. sp., F. minasensis n. sp. e F. dandrophylus n. sp., f. shannoni, F. monticolus, F. pestanai, F. lanei and F. cayenensis constitute a group with many similars characters. F. micropygus is the only American species who present α smaller than β and for that reason and others is allied to. F. minuts and others related species, but presents two terminal spines on the distal segment of the upper clasper. F. micropygus and f. minasensis are quite different because they have very small genitalia, smaller than their heads. F. dendrophylus presents on the median clasper a naked area near the apex and for this and others characters is different from the others of the group. F. flaviscutellatus n. sp., F. oliverioi, F. intermedius and whithmani, are very allied but the first one can be very easily distinguished because it’s scutellum is light. Flebotomus barrettoi n. sp., F. coutinhoi n. sp., F. aragãoi, F. brasiliensis, F. lutzianus, F. texanus, F. pascalei, F. atroclavatus and F. tejeraae are very allied forming a natural group. The two last ones are not well known but the A. A. who have studied them described very long clipeus so long as the head and for that reason can be distinguished from all the others included the two new ones. F. coutinhoi is the only one who presents the apecis of the penis filaments twisted. F. barrettoi n. sp., can be distinguished from aragãoi, texamus and coutinhoi by the length of the penis filaments and from atrocavatus, tejeraae, lutzianus and brasiliensis by the arrangement of the spines of distal segment of the upper clasper. Flebotomus ubiquitalis n. sp., F. auraensis n. sp., F. affinis and F. microps e F. antunesi have many common characters. F. microps n. sp., can be distinguished from any one by the size of the eyes and the presence od well developed genae. This species and other new species are different from F. antunesi by the arrangement of the spines of the distal segment of the upper clasper of the latter. F. ubiquitalis n. sp. can be distinguished from others by the figure of the median clasper. F. auraensis n. sp. Can be distinguished from F. affinis n. sp. By the tuft hairs on the inner face of the basal segment and by arrangement of the spines of the sital segment of the upper clasper. Flebotomus brachipygus n. sp. Seemed to be F. rostrans, specie not well known, by the characters of the genitalia but can not be identified to her by the clypeus size and the palpi’s characters. Flebotomus costalimai, n. sp., f. tupynambai n. sp., and f. castroi Barreto & Coutinho, 1941, are very allied species and the A. proposes to included them the new sub-genus Castromyia, in honor to Dr. G. M. de Oliveira Castro, appointing like typespecies F. castroi with the V joint longer than III + IV; antennae with geniculated spines without posterior prolongation. Genitalia: the basal segment of the upper clasper with a tuft of hairs and the distal segment with 4 spines, one of them at the apex and near it a thin and straight bristle difficult to see; the median clasper with one spinous hair isolated...

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Pathological changes in the vermiform appendix harbouring tapeworm's proglottides are reported. Marked local (tissue) eosinophilia in the stroma of the mucous coat and to a less degree in the sub-mucosa and around the vessels in the inner circular layer of the muscular coat is the essential change observed. Peculiar changes such as an striking increase in the volume of the mucus-producing goblet-cells either in the epithelium covering the free surface or in the glands of Lieberkühn, as well as new epithelium atypical in form and arrangement were noticed in direct connection and likely induced by the tapeworn as a foreign body (mechanical injury). The local (tissue) eosinophilia probably represents an anaphylactoid response to foreign proteins originating in the tapeworm. Acute appendicitis in its recognized varieties such as appendicitis superficalis catarrhalis, a. s. exulcerans, a. s. haemorrhagica, a. phlegmonosa, and a. phlegmonosa-ulcerosa could be microscopically excluded. It seems, however, that local (tissue) eosinophilia when particularly widespread is able to give clinical symtoms suggestive of acute appendicitis.

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Fidena adnaticornis n. sp. is described from female specimens. It closely resembles Fidena besckii (WIED. ), 1828 and indeed more closely Fidena soledadei (LUTZ), 1911. It can be distinguished from both by the antenna which are so close together that the distance between their basis is less that the width of the first antennal segment; also by the prevalence of yellow hairs on the coxae. In F. soledadei and chiefly in F. besckii the antennae an evidently more separated; they have also few yellow hairs limited to the base extremity of the coxae with prevalence of brown or black hairs. In F. besck the prealar hairs are predominantly yellow ones and there exist yellow hair around the edge of the scutellum, which does not occours in F. adnaticorn and in F. soledadei. In the abdomen the following areas, covered by whit hairs are more extensive in F. besckii: the mid row of white patches on the sternites is more conspicuous and involves the fifth segment; on the sternites instead of stripes the hairs form bands somewhat broader at the middle the respective segment, they may even form triangles with the base as with as the whole segment. Both cotypes of F. soledadei have the hairs damages but, at least, in the 1+2 sternites the areas covered by the white hairs see to be larger than in F. adnaticornis; they have also a higher frons: index : = 2.9.

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Our work is on the isolation from brazilian soil of the perfect stage of Microsporum gypseum, Nannizzia gypsea, Stock., 1963, using cut sterilized children hair as bait.

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A new species of South American planorbid snail, Biomphalaria occidentalis, is described. It is indistinguishable from B. tenagophila (Orbigny, 1835), by the characteristics of the shell and of most organs of the genital system. In B. tenagophila there is a pouch on the ventral wall of the vagina (Fig. 4A, vp), absent in B. occidentalis (Fig. 3A), and on the ventral wall of the vagina (Fig. 4A, vp), absent in B. occidentalis (Fig. 3A), and the prepuce is much wider than the penial sheath, its width increasing distalward (Fig. 4, ps,pp), whereas in B. occidentalis the prepuce is wider than the penial sheath but keeps about the same width all along (Fig.3, ps, pp). The two species are biologically separate by absolute reproductive isolation. The geographical distribution of B. occidentalis is shown in Fig. 14. So far it has been found in the Brazilian states of Acre, Amazonas (?), Mato Grosso, Mato Grosso do Sul and Paraná, and in Paraguay. Its type-locality is Campo Grande, state of Mato Grosso do sul, where it was collected from several biotopes related to affluents of the Aquiduana river, chiefly Córrego Prosa and Córrego Ceroula. Specimens were deposited in the following malacological collections: Instituto Oswaldo Cruz, Rio de Janeiro; Academy of Natural Sciences, Philadelphia; Museum of Zoology, University of Michigan; and British Museum (Natural History).

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A new species of South American lymnaeid snail, Lymnaea rupestris, is described. So far it has been found only in its type-locality, Nova TeuTõnia, a village in the municipality of Seara (27° 07' S, 52° 17' W), state of Santa Catarina, Brazil. It is distinguishable, by characteristics of the shell and internal organs, from the other two lymnaeid species known to occur in the area, Lymnaea columella and L. viatrix. Its shell has 4 markedly shouldered whorls, deep suture, ovoid or rounded aperture occupying about half the length of the shell, and reaches about 6 mm in length in adults; in columella and viatrix the shell has 4-5 rounded whorls, shallow suture, and reaches over 10 mm in adults; the aperture is ovoid, occupying about half the length of the shell in viatrix, about two thirds in columella. Anatomically it is readily separated from L. columella by the shape of the ureter, straight in rupestris, with a double flexure in columella. Comparison with L. viatrix shows the following main differences: distalmost portion of the oviduct with a low, caplike lateral swelling in rupestris, with a well-developed pouch in viatrix; uterus bent abruptly caudalward in rupestris, only slightly curved rightward in viatrix; basal half of the spermathecal duct hidden by the prostate in rupestris, wholly visible or nearly so in viatrix; spermiduct sinuous and uniformly wide in rupestris, straight and gradually narrowing in viatrix; prostate more than half as long and nearly as wide as the nidamental gland, and with a slit-like lumen in cross-section in rupestris, less than half as long as and much narrower than the nidamental gland, and with an inward fold in cross-section in viatrix; penial sheath about as long and as wide as the prepuce in rupesris, shorter and narrower than the prepuce in viatrix. An important ecological characteristic of L. rupestris is its habitat on wet rocks most often outside bodies of water, although in close proximity to them. Specimens were deposited in the following malacological collections: Instituto OswaldoCruz, Rio de Janeiro; Academy of Natural Sciences, Philadelphia; Museum of Zoology, University of Michigan; and British Museum (Natural History).

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A description of the species Lymnaea diaphana King, 1830 is presented, on the basis of material collected at its type-locality, San Gregorio, on the north coast of the Strait of Magellan, in the Chilean province of Magallanes. It may be identified by the following characters taken together: adult shell over 10 mm in length, whorls inflated, regularly convex, separated by a well-marked suture, aperture ovate occupying about half the shell length; renal organ forming an approximately right angle with the ureter; pouch of the oviduct well noticeable high on the right ventral surface and on the right side of the nidamental gland; uterus bent to the right into an approximately right angle; body of the spermatheca projected into the pulmonary cavity and adhered to the pericardium and to the roof of the pulmonary cavity; spermiduct highly sinuous, folding dorsalward between the left half of the oviduct and the left shoulder of the nidamental gland, and then winding on ventralward to reach the prostate on the middle line; prostate voluminous, convex on the left, pushed in on the right, with a deep dorsal furrow corresponding to a fold which projects into the prostatic lumen and is more developed at the fore half of the organ; apical end of the penial sheath with about six minute protuberances corresponding to inner chambers; prepuce from about as long about twice as long as the penial sheath, with some variation beyond those limits; lateral teeth of the radula basically tricuspid, with a usually simple ectocone which may show a bifid or trifid point. A diagnosis between lymnaea diaphana and three other lymnaeids which also occur in South America and were previously studied by the author - L. columella, L. viatrix and L. rupestris - is presented.

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A new subspecies of planorbid snail, biomphalaria tenagophila guaibensis, is described. It has been found along the coastal belt of the Brazilian state of rio grande do Sul and the middle part of Uruguay, from Porto Alegre to Mercedes. It differs from the nominate subspecies, Biomphalaria tenagophila tenagophila, in the appearance of the penial complex (prepuce longer and proportionally slenderer in B. t. guaibensis, shorter and proportionally stouter in b. t. tenagophila), in the ratio between the lengths of the penial sheath and the prepuce, in the ratio between the lengths of the uterine complex and the penial complex, and in a coefficient of difference of 2.44 for the ratio between the penis sheath and prepuce and of 2.02 for the ratio between the uterine complex and penial complex. The shell and the other organs of the genital system are similar in both subspecies. B. t. guaibensis is very similar to Biomphalaria occidentalis Paraense, 1981, but is readily separated from it by the presence of a vaginal pouch, which is lacking in the latter, besides showing highly significant difference in the penis sheath: prepuce and uterine complex: penial complex ratios. Crossbreeding experiments which lend additional support to the recognition of B. t. guaibensis as a subspecies will be reported elsewhere.

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A description of Physa marmorata Guilding, 1828, based on material collected at its type-locality, the Caribbean island of Saint Vincent, is presented. The shell is thin, horn-colored, surface very glossy, diaphanous. Spire acute, elevated; protoconch distinct, rounded-conical, reddish-brown; five not shouldered, broadly convex whorls with subobsolete spiral lines and thin growth lines. Aperture elongated, 1.4-2.0 times as long as the remaining shell length, narrow obovate-lunate; upper half acute-angled,lower half oval,narrowly rounded at the base, outer lip sharp, inner lip completely closing the umbilical region; a very distinct callus on the parietal wall; columellar lip with a low ridge gradually merging into the callus. ratios: shell width/shell length = 0.44 - 0.52 (mean 0.47); spire length /shell lenght = 0.33-0.41 (mean 0.39); aperture length/shell lenght = 0.59-0.67 (mean 0.62). Oral lappets laterally mucronate, foot spatulate with deeply pigmented acuminate tail. Mantle reflection with 6-10 short triangular dentations covering nearly half the right surface of the body whorl, and 4-6 covering a part of the ventral wall. Body surface with tiny dots of greenish-yellow pigment besides melanin. Renal tube tightly folded in toa zigzag course. Ovotestis diverticula acinous, laterally pressed against each other around a collecting canal. Ovispermiduct with well-developed seminal vesicle. oviduct highly convoluted, merging into a less convoluted nidamental gland which narrows to a funnel-shaped uterus and a short vagina. Spermathecal body oblong, more or less constricted in the middle and somewhat curved; spermathecal duct uniformly narrow, a little longer than be body. About 20 prostatic diverticula, simple, bifurcate or divided into a few short branches, distalmost ones assembled into a cluster. Penis long, nearly uniformly narrow; penial canal with lateral opening about the junction of its middle and lower thirds. Penial sheath with a bulbous terminal expasion the tip of which isinserted into the caudal end of the prepuce. Prepuce shouldered, much wider than the narrow portion of the penial sheath. Penial sheath/prepuce ratio about 2.08 (1.45-2.75). The main extrinsic muscles of the penial complex are a retractor, with a branch attached to the bulb, and another to the caudal end of the penial sheath; and a protractor, with a branch attached to the shoulder of the prepuce and adjoining area of the penial sheath, and another to the caudal end of the penial sheath. Egg capsule C-shaped, with 10-30 elliptical eggs (snails 10mm long) measuring about 1.10 mm (0.90-1.32) through the long axis and surrounded by an inner and an outer lamellate membranes. Jaw a simple obtusely V-shaped plate. radula will be described separately.

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Organs developing as appendages of the ectoderm are initiated from epithelial thickenings called placodes. Their formation is regulated by interactions between the ectoderm and underlying mesenchyme, and several signalling molecules have been implicated as activators or inhibitors of placode formation. Ectodysplasin (Eda) is a unique signalling molecule in the tumour necrosis factor family that, together with its receptor Edar, is necessary for normal development of ectodermal organs both in humans and mice. We have shown previously that overexpression of the Eda-A1 isoform in transgenic mice stimulates the formation of several ectodermal organs. In the present study, we have analysed the formation and morphology of placodes using in vivo and in vitro models in which both the timing and amount of Eda-A1 applied could be varied. The hair and tooth placodes of K14-Eda-A1 transgenic embryos were enlarged, and extra placodes developed from the dental lamina and mammary line. Exposure of embryonic skin to Eda-A1 recombinant protein in vitro stimulated the growth and fusion of placodes. However, it did not accelerate the initiation of the first wave of hair follicles giving rise to the guard hairs. Hence, the function of Eda-A1 appears to be downstream of the primary inductive signal required for placode initiation during skin patterning. Analysis of BrdU incorporation indicated that the formation of the epithelial thickening in early placodes does not involve increased cell proliferation and also that the positive effect of Eda-A1 on placode expansion is not a result of increased cell proliferation. Taken together, our results suggest that Eda-A1 signalling promotes placodal cell fate during early development of ectodermal organs.

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A description of Physa cubensis Pfeiffer, 1839, based on 15 speciments collected in Havana, Cuba, is presented. The shell, measuring 9.0 x 4,8mm to 12.3 x 6.4mm, is ovate-oblong, thin, diaphanous, horncolored, shining. Spire elevated, broadly conical; protoconch distinct, roundish, reddish-brown. About five moderately shouldered, roundly convex whorls, penultimate whorl expanded; spiral striation subobsolete; growth line faint on the intermediate whorls, clearly visible on the body whorl, crowded here and there. Suture well impressed. Aperture elongated 2.05 - 2.67 (mean 2.27) times as long as the remaining length of the shell, narrow obovulate-lunate; upper half acute-angled, lower half oval, narrowly rounded at the base; outer lip sharp, inner lip completely closing the umbilical region; a thick callus on the parietal wall; columellar plait well marked. Ratios: shell width/shell length - 0.52-0.61 (mean 0.55); spire length/shell length = 0.27 - 0.33 (mean 0.31); aperture length/shell length = 0.67 - 0.73 (mean 0.69). Oral lappets laterally mucronate; foot spatulate with acuminate tail. Mantle relection with 6 - 8 short triangular dentations in the right lobe (columellar side) and 4 - 6 in the left lobe (near the pneumostome). Renal tube tightly folded into a zigzag course. Ovotestis, ovispermiduct, seminal vesicle, oviduct, nidamental gland, uterus and vagina as in Physa marmorata (see Paraense, 1986, Mem. Inst. Oswaldo Cruz, 81: 459-469). Spermathecal body egg-shaped or pear-shaped; spermathecal ducta uniformly narrow with expanded base, a little longer than the body. Spermiduct, prostate and vas deferens as in P. marmorata (Paraense, loc. cit.). Penis wide proximally, narrowing gradually apicad; penial canal with subterminal outlet. Penial sheath following the width of the penis and ending up by a bulbous expansion somewhat narrower than the proximal portion. Penaial sheath/prepuce ration = 1,25 - 1,83 (mean 1.49). Prepuce much wider than the bulb of the penial shealth, moderately shouldered owing to the intromission of the bulb, and with a large gland in one side of its proximal half occupating about a third of its length. Extrinsic muscles of the penial complex as in P. marmorata. Jaw a simple obtusely V-shaped plate. Radula to be described separetely.