59 resultados para Tongue biofilm
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The neurohistologic observations were performed using the specimens prepared by Winkelmann and Schmitt silver impregnation method. The tissues were fixed in 10% formalin solution and sections of 40µm thickness were obtained by Leica Cryostat at -30ºC. The sections of dorsal mucosa of White-lipped peccary tongue showed numerous filliform and fungiform papillae, and two vallate papillae on the caudal part. The epithelial layer revealed queratinized epithelial cells and the connective tissue papillae of different sizes and shapes. Thick nerve fiber bundles are noted into the subepithelial connective tissue of the papillae. The connective tissue of fungiform and vallate papillae contained numerous sensitive nerves fibers bundles forming a complex nerve plexus.
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To verify the occurrence of caseous lymphadenitis in sheep and goats on farms of Pernambuco, Brazil, and in animals slaughtered in two Brazilian cities (Petrolina/PE and Juazeiro/BA), and to characterize the susceptibility profile of Corynebacterium pseudotuberculosis to disinfectants and antimicrobials, and its relationship with biofilm production were the objectives of this study. 398 samples were tested for sensitivity to antimicrobial drugs, disinfectants, and biofilm production. Among the 108 samples collected on the properties, 75% were positive for C. pseudotuberculosis. Slaughterhouse samples indicated an occurrence of caseous lymphadenitis in 15.66% and 6.31% for animals slaughtered in Petrolina and Juazeiro respectively. With respect to antimicrobials, the sensitivity obtained was 100% for florfenicol and tetracycline; 99.25% for enrofloxacin, ciprofloxacin and lincomycin; 98.99% for cephalothin; 98.74% for norfloxacin and sulfazotrim; 97.74% for gentamicin; 94.22% for ampicillin; 91.71% for amoxicillin; 91.21% for penicillin G; 89.19% for neomycin and 0% for novobiocin. In analyzes with disinfectants, the efficiency for chlorhexidine was 100%, 97.20% for quaternary ammonium, 87.40% for chlorine and 84.40% for iodine. 75% of the isolates were weak or non-biofilm producers. For the consolidated biofilm, found that iodine decreased biofilm formation in 13 isolates and quaternary ammonia in 11 isolates. The reduction of the biofilm formation was observed for iodine and quaternary ammonium in consolidated biofilm formation in 33% and 28% of the isolates, respectively. The results of this study highlight the importance of establishing measures to prevent and control the disease.
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Biofilms constitute a physical barrier, protecting the encased bacteria from detergents and sanitizers. The objective of this work was to analyze the effectiveness of sodium hypochlorite (NaOCl) against strains of Staphylococcus aureus isolated from raw milk of cows with subclinical mastitis and Staphylococcus aureus isolated from the milking environment (blowers and milk conducting tubes). The results revealed that, in the presence of NaOCl (150ppm), the number of adhered cells of the twelve S. aureus strains was significantly reduced. When the same strains were evaluated in biofilm condition, different results were obtained. It was found that, after a contact period of five minutes with NaOCl (150ppm), four strains (two strains from milk , one from the blowers and one from a conductive rubber) were still able to grow. Although with the increasing contact time between the bacteria and the NaOCl (150ppm), no growth was detected for any of the strains. Concerning the efficiency of NaOCl on total biofilm biomass formation by each S. aureus strain, a decrease was observed when these strains were in contact with 150 ppm NaOCl for a total period of 10 minutes. This study highlights the importance of a correct sanitation protocol of all the milk processing units which can indeed significantly reduce the presence of microorganisms, leading to a decrease of cow´s mastitis and milk contamination.
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Abstract: Rhodococcus equi is a facultative intracellular pathogen, which cause severe pyogranulomatous pneumonia in foals and tuberculosis-like lesions in humans. Its ability to form biofilm was described in strains isolated from chronic diseases associated to treatment failures in humans. This study aimed to verify the biofilm formation by 113 R. equi isolated from equine samples (clinical and fecal) using two different methods (biofilm-culturing with and without additional glucose and epifluorescence microscopy). We also aimed to determine the efficacy of azithromycin, clarithromycin and erythromycin on R. equi in established biofilm. We found 80.5% (26/41) and 63% (58/72) biofilm-positive isolates, in fecal and clinical samples, respectively. The additional glucose increased the biofilm formation by R. equi fecal samples, but not by clinical samples. The antimicrobials tested herein were not able to eradicate R. equi in biofilm even at higher concentrations. This is the first study showing the biofilm formation by R. equi isolated from equine samples. Our findings indicate that R. equi biofilm-producers may be more resistant to the antimicrobials evaluated. Further studies are warranted to test this hypothesis.
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Staphylococcus spp. can survive in biofilms for long periods of time, and they can be transferred from one point to another and cause environmental contamination in food processing. The aim of this study was to detect Staphylococcus strains isolated from a poultry processing plant by the presence of adhesion genes and the phenotypic production of exopolysaccharide. In the present study, the production of exopolysaccharide and the presence of adhesion genes in 65 strains of Staphylococcus spp. were evaluated. All strains of Staphylococcus spp. produced exopolysaccharide, as confirmed by formation of black and opaque colonies in Congo Red Agar. The variation of sucrose content was critical for the production of exopolysaccharide in Congo Red Agar since at low sucrose concentrations all strains presented a characteristic result, i.e., there was no exopolysaccharide production. The atl gene was found in all strains, and the icaA and icaD genes were found in 97% of them. The data obtained suggest that Staphylococcus spp. isolated from the poultry processing plant evaluated has a potential for biofilm formation. An efficient control of this microorganism in food processing environment is necessary as they may represent a potential risk to consumers.
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Systematic examination of the upper respiratory and digestive tracts (URDT) was performed in a group of 80 paracoccidioidomycosis (PCM) patients submitted to post-treatment follow-up ranging from 8 months to 17 years. Mucosae of the URDT had been involved prior to specific treatment in 74 patients, distributed as follows: oropharynx, 50 (41 alone, 7 in association with the larynx, and 2 with the nasal mucosa); larynx, 30 (23 alone and 7 in association); and nasal mucosa, 3(1 alone and 2 in association). Inactive lesions were observed in all the 50 patients with lesions of the oropharynx, 3 of whom with deforming scars (1 with retraction of the tongue and 2 with narrowing of the oral orifice). One case presented a destructive lesion, with perfuration of the palate. Of the other 46 cases, examination showed nacreous white striated scars which were nearly imperceptible in some cases and in others displayed partial retraction of anatomical structures without any alteration of their features. Patients presented a high rate of missing teeth. In 3 patients with involvement of the nasal mucosa, none of whom presented active PCM lesions, 2 still had nasal voices. In 30 patients with lesions of the larynx, 1 suffered a relapse of PCM and 2 developed epidermoid carcinoma. Of the other 27 cases, none of whom had active PCM lesions, 15 presented dysphonia, 3 were tracheotomized, and 9 were asymptomatic.
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Cysticercosis is a condition that occurs when man is infested by the larvae of Taenia solium, acting as an intermediate host instead of definitive. Oral cysticercosis is a rare event, and it represents a difficulty in clinical diagnosis. A case of oral cysticercosis in a 23-year-old white female who presented a painless swelling in the dorsal portion of the tongue is reported. An excisional biopsy was performed and histopathological examination revealed a cystic cavity containing the tapeworm.
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Involvement of the digestive system in patients with acquired immunodeficiency syndrome (AIDS) is frequent and many changes in these patients are diagnosed only at autopsy. There are few studies of autopsy with detailed analysis of this system and only one was conducted in Brazil. We evaluated each segment of the digestive system in 93 consecutive autopsies of patients infected with human immunodeficiency virus (HIV) and the importance of these lesions to death. Of these, 90 (96.8%) patients had AIDS. We reviewed medical records, autopsy reports and histological sections from tongue to rectum stained with hematoxylin-eosin. When necessary, we analyzed special stains and immunohistochemistry to investigate infections. There was damage to the digestive system in 73 (78.5%) cases. The most common infections were candidiasis (42%), cytomegalovirus (29%), histoplasmosis (11.8%), toxoplasmosis (9.7%) and mycobacterial infection (9.7%). Malignancies were rare, present in four (4.3%) cases (two Kaposi's sarcoma, one adenocarcinoma and one metastatic embryonal carcinoma). All segments showed lesions: tongue (48.6%), esophagus (44.8%), stomach (44.7%), colon (43.2%) and small intestine (28.9%). The lesions found were immediate cause of death in five (5.4%) cases. In another 36 (38.7%) cases the basic disease was systemic and also compromised the digestive system.
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We report the case of a 35-year-old homeless alcoholic and illicit drug user, with AIDS, who was admitted to the emergency unit complaining of asthenia and a weight loss of 30kg over the preceding three months. Clinical and laboratory data confirmed a diagnosis of marasmus, bacterial pneumonia, chorioretinitis caused by Toxoplasma gondii and oral Candida infection. The patient also presented loss of tongue papillae, gingival hypertrophy, perifollicular hyperkeratosis and hemorrhage, coiled, corkscrew-like hair, anemia, hypoalbuminemia, increased C-reactive protein levels and low serum vitamin C levels. The patient developed severe gastric hemorrhage, with hemodynamic instability and terminal disseminated intravascular coagulopathy.
Synergistic interactions in mixed-species biofilms of pathogenic bacteria from the respiratory tract
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IntroductionMixed-species biofilms are involved in a wide variety of infections. We studied the synergistic interactions during dual-species biofilm formation among isolates of Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia.MethodsIsolates were cultured as single-species and all possible combinations of dual-species biofilms.ResultsThe 61 A. baumannii biofilms increased by 26-fold when cultured with S. maltophilia isolates; 62 A. baumannii biofilms increased by 20-fold when cultured with S. maltophilia isolates; and 31 P. aeruginosa biofilms increased by 102-fold when cultured with S. maltophilia 106.ConclusionsSynergy was observed between two isolates, including those that inherently lacked biofilm formation ability.
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ABSTRACTINTRODUCTION:Exposure to subinhibitory concentrations (SICs) of antimicrobials may alter the bacterial transcriptome.METHODS: Here, we evaluated the expression of nine virulence-related genes in vancomycin-resistant enterococci (VRE) urinary tract infection isolates grown at SICs of vancomycin.RESULTS:A Subinhibitory concentrations of vancomycin interferes with gene modulation, but does not affect the phenotype of a VRE strain in vitro .CONCLUSIONS:Subinhibitory concentrations of vancomycin may regulate the expression of virulence factors in vivo or contribute to the selection of vancomycin-resistant strains.
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Abstract: INTRODUCTION: This study assessed the prevalence of hypovitaminosis D and its association with oral candidiasis and clinical parameters of periodontitis (CPP) in HIV-infected patients. METHODS: Periodontal examinations for the 113 HIV-infected patients were recorded using the Community Periodontal Index. A cytological smear from the lateral borders of the tongue was performed to evaluate candidiasis. RESULTS: The frequency of hypovitaminosis D was 23.9%. In multivariate analysis, only the duration of exposure to HIV was associated with CPP [OR 4.72 (95% CI: 0.97-23.00)]. CONCLUSIONS: The prevalence of hypovitaminosis D was 23.9% and was not related with oral candidiasis or CPP.
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A nest of an undescribed species of Euglossa was found inside a fruit of Theobroma subincanum (Sterculiaceae) in the Amazonian rainforest, Ecuador. It contained 3-4 living females and one dead and 37 cells in all. Total length of bee 12.5mm; frons blue-green; thorax blue; abdomen bronze above, green and dark ventrally; and kind tibia blue. Tongue about 11 mm long.
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This paper deals with problems on population genetics in Hymenoptera and particularly in social Apidae. 1) The studies on populations of Hymenoptera were made according to the two basic types of reproduction: endogamy and panmixia. The populations of social Apinae have a mixed method of reproduction with higher percentage of panmixia and a lower of endogamy. This is shown by the following a) males can enter any hive in swarming time; b) males of Meliponini are expelled from hives which does not need them, and thus, are forced to look for some other place; c) Meliponini males were seen powdering themselves with pollen, thus becoming more acceptable in any other hive. The panmixia is not complete owing to the fact that the density of the breeding population as very low, even in the more frequent species as low as about 2 females and 160 males per reproductive area. We adopted as selection values (or survival indices) the expressions according to Brieger (1948,1950) which may be summarised as follows; a population: p2AA + ²pq Aa + q2aa became after selection: x p2AA + 2pq Aa + z q²aa. For alge-braics facilities Brieger divided the three selective values by y giving thus: x/y p2 AA + y/y 2 pq Aa + z/y q²aa. He called x/y of RA and z/y of Ra, that are survival or selective index, calculated in relation to the heterozygote. In our case all index were calculated in relation to the heterozygote, including the ones for haploid males; thus we have: RA surveval index of genotype AA Ra surveval index of genotype aa R'A surveval index of genotype A R'a surveval index of genotype a 1 surveval index of genotype Aa The index R'A ande R'a were equalized to RA and Ra, respectively, for facilities in the conclusions. 2) Panmitic populations of Hymenoptera, barring mutations, migrations and selection, should follow the Hardy-Weinberg law, thus all gens will be present in the population in the inicial frequency (see Graphifc 1). 3) Heterotic genes: If mutation for heterotic gene ( 1 > RA > Ra) occurs, an equilibrium will be reached in a population when: P = R A + Ra - 2R²a _____________ (9) 2(R A + Ra - R²A - R²a q = R A + Ra - 2R²A _____________ (10) 2(R A + Ra - R²A - R²a A heterotic gene in an hymenopteran population may be maintained without the aid of new mutation only if the survival index of the most viable mutant (RA) does not exced the limiting value given by the formula: R A = 1 + √1+Ra _________ 4 If RA has a value higher thah the one permitted by the formula, then only the more viable gene will remain present in the population (see Graphic 10). The only direct proof for heterotic genes in Hymenoptera was given by Mackensen and Roberts, who obtained offspring from Apis mellefera L. queens fertilized by their own sons. Such inbreeding resulted in a rapid loss of vigor the colony; inbred lines intercrossed gave a high hybrid vigor. Other fats correlated with the "heterosis" problem are; a) In a colony M. quadrifasciata Lep., which suffered severely from heat, the percentage of deths omong males was greater .than among females; b) Casteel and Phillips had shown that in their samples (Apis melifera L). the males had 7 times more abnormalities tian the workers (see Quadros IV to VIII); c) just after emerging the males have great variation, but the older ones show a variation equal to that of workers; d) The tongue lenght of males of Apis mellifera L., of Bombus rubicundus Smith (Quadro X), of Melipona marginata Lep. (Quadro XI), and of Melipona quadrifasciata Lep. Quadro IX, show greater variationthan that of workers of the respective species. If such variation were only caused by subviables genes a rapid increasse of homozigoty for the most viable alleles should be expected; then, these .wild populations, supposed to be in equilibrium, could .not show such variability among males. Thus we conclude that heterotic genes have a grat importance in these cases. 4) By means of mathematical models, we came to the conclusion tht isolating genes (Ra ^ Ra > 1), even in the case of mutations with more adaptability, have only the opor-tunity of survival when the population number is very low (thus the frequency of the gene in the breeding population will be large just after its appearence). A pair of such alleles can only remain present in a population when in border regions of two races or subspecies. For more details see Graphics 5 to 8. 5) Sex-limited genes affecting only females, are of great importance toHymenoptera, being subject to the same limits and formulas as diploid panmitic populations (see formulas 12 and 13). The following examples of these genes were given: a) caste-determining genes in the genus Melipona; b) genes permiting an easy response of females to differences in feeding in almost all social Hymenoptera; c) two genes, found in wild populations, one in Trigona (Plebéia) mosquito F. SMITH (quadro XII) and other in Melipona marginata marginata LEP. (Quadro XIII, colonies 76 and 56) showing sex-limited effects. Sex-limited genes affecting only males do not contribute to the plasticity or genie reserve in hymenopteran populations (see formula 14). 6) The factor time (life span) in Hymenoptera has a particular importance for heterotic genes. Supposing one year to be the time unit and a pair of heterotic genes with respective survival indice equal to RA = 0, 90 and Ra = 0,70 to be present; then if the life time of a population is either one or two years, only the more viable gene will remain present (see formula 11). If the species has a life time of three years, then both alleles will be maintained. Thus we conclude that in specis with long lif-time, the heterotic genes have more importance, and should be found more easily. 7) The colonies of social Hymenoptera behave as units in competition, thus in the studies of populations one must determine the survival index, of these units which may be subdivided in indice for egg-laying, for adaptive value of the queen, for working capacity of workers, etc. 8) A study of endogamic hymenopteran populations, reproduced by sister x brother mating (fig. 2), lead us to the following conclusions: a) without selection, a population, heterozygous for one pair of alleles, will consist after some generations (theoretically after an infinite number of generation) of females AA fecundated with males A and females aa fecundated with males a (see Quadro I). b) Even in endogamic population there is the theoretical possibility of the presence of heterotic genes, at equilibrium without the aid of new mutations (see Graphics 11 and 12), but the following! conditions must be satisfied: I - surveval index of both homozygotes (RA e Ra) should be below 0,75 (see Graphic 13); II - The most viable allele must riot exced the less viable one by more than is permited by the following formula (Pimentel Gomes 1950) (see Gra-fic 14) : 4 R5A + 8 Ra R4A - 4 Ra R³A (Ra - 1) R²A - - R²a (4 R²a + 4 Ra - 1) R A + 2 R³a < o Considering these two conditions, the existance of heterotic genes in endogamic populations of Hymenoptera \>ecames very improbable though not - impossible. 9) Genie mutation offects more hymenopteran than diploid populations. Thus we have for lethal genes in diploid populations: u = q2, and in Hymenoptera: u = s, being u the mutation ratio and s the frequency of the mutant in the male population. 10) Three factors, important to competition among species of Meliponini were analysed: flying capacity of workers, food gathering capacity of workers, egg-laying of the queen. In this connection we refer to the variability of the tongue lenght observed in colonies from several localites, to the method of transporting the pollen in the stomach, from some pots (Melliponi-ni storage alveolus) to others (e. g. in cases of pillage), and to the observation that the species with the most populous hives are almost always the most frequent ones also. 11) Several defensive ways used for Meliponini to avoid predation are cited, but special references are made upon the camouflage of both hive (fig. 5) and hive entrance (fig. 4) and on the mimetism (see list in page ). Also under the same heading we described the method of Lestrimelitta for pillage. 12) As mechanisms important for promoting genetic plasticity of hymenopteran species we cited: a) cytological variations and b) genie reserve. As to the former, duplications and numerical variations of chromosomes were studied. Diprion simile ATC was cited as example for polyploidy. Apis mellife-ra L. (n = 16) also sugests polyploid origen since: a) The genus Melipona, which belongs to a" related tribe, presents in all species so far studied n = 9 chromosomes and b) there occurs formation of dyads in the firt spermatocyte division. It is su-gested that the origin of the sex-chromosome of Apis mellifera It. may be related to the possible origin of diplo-tetraploidy in this species. With regards to the genie reserve, several possible types of mutants were discussed. They were classified according to their survival indices; the heterotic and neutral mutants must be considered as more important for the genie reserve. 13) The mean radius from a mother to a daghter colony was estimated as 100 meters. Since the Meliponini hives swarm only once a year we may take 100 meters a year as the average dispersion of female Meliponini in ocordance to data obtained from Trigona (tetragonisca) jaty F. SMITH and Melipona marginata LEP., while other species may give different values. For males the flying distance was roughly estimated to be 10 times that for females. A review of the bibliography on Meliponini swarm was made (pg. 43 to 47) and new facts added. The population desity (breeding population) corresponds in may species of Meliponini to one male and one female per 10.000 square meters. Apparently the males are more frequent than the females, because there are sometimes many thousands, of males in a swarm; but for the genie frequency the individuals which have descendants are the ones computed. In the case of Apini and Meliponini, only one queen per hive and the males represented by. the spermatozoos in its spermateca are computed. In Meliponini only one male mate with the queen, while queens of Apis mellijera L. are fecundated by an average of about 1, 5 males. (Roberts, 1944). From the date cited, one clearly sees that, on the whole, populations of wild social bees (Meliponini) are so small that the Sewall Wright effect may become of great importance. In fact applying the Wright's formula: f = ( 1/aN♂ + 1/aN♀) (1 - 1/aN♂ + 1/aN♀) which measures the fixation and loss of genes per generation, we see that the fixation or loss of genes is of about 7% in the more frequent species, and rarer species about 11%. The variation in size, tergite color, background color, etc, of Melipona marginata Lep. is atributed to this genetic drift. A detail, important to the survival of Meliponini species, is the Constance of their breeding population. This Constance is due to the social organization, i. e., to the care given to the reproductive individuals (the queen with its sperm pack), to the way of swarming, to the food storage intended to control variations of feeding supply, etc. 14) Some species of the Meliponini are adapted to various ecological conditions and inhabit large geographical areas (e. g. T. (Tetragonisca jaty F. SMITH), and Trigona (Nanno-trigona testaceicornis LEP.) while others are limited to narrow regions with special ecological conditions (e. g. M. fuscata me-lanoventer SCHWARZ). Other species still, within the same geographical region, profit different ecological conditions, as do M. marginata LEP. and M. quadrifasciata LEP. The geographical distribution of Melipona quadrifasciata LEP. is different according to the subspecies: a) subsp anthidio-des LEP. (represented in Fig. 7 by black squares) inhabits a region fron the North of the S. Paulo State to Northeastern Brazil, ,b) subspecies quadrifasciata LEP., (marked in Fig. 7 with black triangles) accurs from the South of S. Paulo State to the middle of the State of Rio Grande do Sul (South Brazil). In the margined region between these two areas of distribution, hi-brid colonies were found (Fig. 7, white circles); they are shown with more details in fig. 8, while the zone of hybridization is roughly indicated in fig. 9 (gray zone). The subspecies quadrifasciata LEP., has 4 complete yellow bands on the abdominal tergites while anthidioides LEP. has interrupted ones. This character is determined by one or two genes and gives different adaptative properties to the subspecies. Figs. 10 shows certains meteorological isoclines which have aproximately the same configuration as the limits of the hybrid zone, suggesting different climatic adaptabilities for both genotypes. The exis-tance of a border zone between the areas of both subspecies, where were found a high frequency of hybrids, is explained as follows: being each subspecies adapted to a special climatic zone, we may suppose a poor adaptation of either one in the border region, which is also a region of intermediate climatic conditions. Thus, the hybrids, having a combination of the parent qualities, will be best adapted to the transition zone. Thus, the hybrids will become heterotic and an equilibrium will be reached with all genotypes present in the population in the border region.
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Hyla claresignata Lutz & Lutz, 1939, is a large species apparently not closely allied to the other known Brazilian hylas. It is characterized by the very small tympanum; the head is short and the snout rounded; the legs are long, the hands and feet unusually large, the latter extensively webbbed. The specific name is derived from the insular, irregular, or roughly triangular, dark spots, with a light halo, found mostly in the dorso-lateral region and on the legs. It belongs to the rain-forest fauna of the Marítime Range. The adult is a bromeliad-dweller and the tadpole rhyacophilous. DESCRIPTION. Vomerine teeth in two separate, oblique, groups, behind the large choanae, parallel to the posterior half of their inner border. Tongue entire, short, very broad and hardly free behind. Snout short, rounded, with distinct canthus rostralis and gradually sloping loreal region. Eye very large and prominent, its horizontal diameter almost equal to the distance between its anterior corner and the tip of the snout. Tympanum very small, less than one third of the diameter of the eye, but distinct, partly covered by a short, heavy ridge. Lateral fingers less than one third webbed; fourth finger slightly longer than the second, just reaching the base of the disk of the third; subarticular tubercles well developed; an angular pollex rudiment, more noticeable in the males. Toes almost completely webbed, the edge of the web inserted at the base of the disk on the third and the fifth; an inner metatarsal tubercle. Skin smooth above, granular beneath, on the throat minutely so. No dermal appendage on the hell. Habit robust, head broader than long, body rather heavy, slightly narrowed in the postaxillary region. Legs long, the tibiotarsal articulation reaching beyond the tip of the snout when adpressed. Type (female): 61 mm. (Fig. 1.) DIAGNOSIS of TADPOLE (by G. Orton). "A large specialized, mountain-stream tadpole, with wide head an elongated, flattened snout, greatly enlarged lips and high tooth formula. Eyes dorsal. Spiracle sinistral, projecting, situated far back on side. Anus dextral. Tooth formula 8/12 to 9/14 in fully grown larvae. Tail with a prominent, vertical dark band across musculature and fins; a second concentration of dark pigment near tip of tail, may or may not form a similar but narrower band. Maximum known total length: 60mm.; head and body length 25mm. (Figs. 6 e 7). For further details see Lutz & Lutz, 1939 and Lutz B. & Orton G. 1946.