Species, genera et ordines algarum : seu descriptiones succinctae specierum, generum et rodinum, quibus algarum regnum constituitur / auctore Jacobo Georgio Agardh.

v.3 pt.3

III - Contribuição para o estudo biológico e ecológico das Podostemaceae do salto do Piracicaba

1 - The Author, in this 3 thd. contribution, concludes the study of the biology and ecology of the species Tristicha trifaria (Willd.) Spreng. and Mourera aspera (Bong.) Tul., both of the Piracicaba Fall. 2 - According to the results of Dr. Peter van Royen (State Herbarium of Leiden, Holland), who made a complete revision of Podostemaceae of the Piracicaba Fall, the species Tristicha hypnoides (St. Hil.) Spreng. var. Hilarii Tul. and Mnioppsis Glazioviana Warm, correspond, respectively, to theTristicha trifaria (Willd.) Spreng. and Mniopsis weddelliana Tul. Apinagia Accorsii Toledo was transferred by Royen to the genus Wettsteiniola. So, its new name is Wettsteiniola accorsii (Toledo) v. Royen. 3 - Propagation by seeds may occur in the following places: a) placenta of partially open fruits; b) external and internal walls of the open capsules; c) pedicels of the fruits; d) remains of rhizomes, branches, etc. e) organic residues accumulated in water holes in the fall; f) clean rocks, in which the little groups of seedlings seems to be a colony of algae. Seeds adhere to the substrata above by means, of a mucilage produced by the transformation of the external integuments in contact with water. 4 - In the growth of the four species below it was found in Piracicaba Fall conspicuous zoning so scattered: a) Wettsteiniola accorsii (Toledo) v. Royen, in rocks situated just within the water fall, where velocity of the current and aeration of the water are very high. b) Tristicha trifaria (Willd.) Spreng. and Mniopsis weddelliana Tul., in rocks at some distance (100 m more or less) upstream until near the bridge across the river. c) Mourera aspera (Bong.) Tul., 300 m upwards the bridge. 5- During 1949, the ecological conditions of the Piracicaba Fall were changed due to the following factors: a) dry season very long, begining from last period of June until 30 november; b) stopping, during four months, of water from the Atibaia river (one of the components of Piracicaba river) near to the city of Americana, in the place where a new station of the Companhia Paulista de Força e Luz was build. In consequence, most of the Podostemaceae died. On the dry rocks there were only fruits and dried plants. 6 - Tristicha trifaria has the same biological and ecological behavior as the Mniopsis weddelliana,. 7 - The vegetative propagation of Tristicha trifaria is made by increasing of its branches, production of stolons with vegetatives buds and regeneration of old parts in especial conditions of water and aeration. 8 - Mourera aspera has the same vegetative propagation as the Wettsteiniola accorsii; it produces stolons (in very little percentage) with vegetative buds, branches of the rhizomes and regeneration of active old parts. 9 - Frequently, there is, on the plants an accumulation of sand, silt, loam, organic substances, and so on. The quantity of material stored depends of the purity of the water, of the morphology of the plants and of the situation on the fall. 10 - In extrem conditions of dry heat, the surviving of the species in its habitat depends exclusively from germination of seeds in the mentioned substrata. Exceptionally, some plants survive in a few water pockets full with the weak remaining current.

The filamentous Myxophyceae of Jamaica, by Francis Drouet.

v.20:no.5(1942)

The Myxophyceae of Maryland, by Francis Drouet.

v.20:no.1(1939)

Some lower Huronian stromatolites of northern Michigan / Eugene S. Richardson, Jr. --

v.10:no.8(1949)

Feeding of two Cichlidae species (Perciformes) in an hypertrophic urban lake

Diet of two cichlid species, Cichlasoma facetum (Jenyns, 1842), and Gymnogeophagus rhabdotus Hensel, 1870, was studied in Rodó Lake, an urban hypertrophic lake in Uruguay. The stomach contents from 192 individuals of C. facetum and 202 of G. rhabdotus, obtained through seasonal sampling in the year 2000, were analyzed. The occurrence frequency and the alimentary importance index of each food item were calculated for each season and size class in both species. Cichlasoma facetum fed upon insects (mainly chironomid larvae and pupae), fish (Cnesterodon decemmaculatus Jenyns, 1842), and vegetals (algae, periphyton and macrophytes debris); large individuals also fed upon the freshwater shrimp Palaemonetes argentinus Nobili, 1901. Gymnogeophagus rhabdotus consumed zooplankton (mainly copepods), vegetals (algae and detritus) and Chironomidae larvae in a lesser extent.

Biologia alimentar de Steindachnerina brevipinna (Characiformes, Curimatidae) do rio Ibicuí-mirim, Rio Grande do Sul, Brasil

The feeding biology of Steindachnerina brevipinna (Eigenmann & Eigenmann, 1889) is described based on specimens collected in the Ibicuí-Mirim river, Rio Grande do Sul, Brazil, from April 2001 to March 2002. Diet description is based on the analysis of the frequency of occurrence and index of dietary importance of the ingested items. The monthly variation of stomach repletion, hepatosomatic and intestinal indexes was also analyzed. Major feeding activity occurred before (May, June and July 2001) the reproductive period, with the hepatosomatic index values showing similar variation along the year. Both the mean intestinal quotient and the analysis of the main ingested items (Bacillariophyta and Chlorophyta algae) indicate a detritivorous diet.

Organic buildups in the Lower Ordovician (Canadian) of Texas and Oklahoma / Donald Francis Toomey -- and Matthew H. Nitecki --.

n.s. no.2(1979)

Ordovician Receptaculites camacho n. sp. from Argentina / Matthew H. Nitecki -- and Gerald G. Forney --.

v.37:no.5(1978)

Internal structures of Cyclocrinites dactioloides : a receptaculitid alga from the Lower Silurian of Iowa / Matthew H. Nitecki -- and Markes E. Johnson --.

v.39:no.1(1978)