Ceylon Journal of Science (Biological Sciences)
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Item Annelida polychaeta from the Philippines and Indonesia(University of Peradeniya. Peradeniya, 1965) Pillai, T.G.Item The food of the tadpoles of Rhacophorus cruciger cruciger (Blyth)(University of Peradeniya. Peradeniya, 1965) Costa, H.H.; Balasubramaniam, S.1) Examination of food in the alimentary canal of Rhacophorus tadpoles showed that the plankton algae present in the water were ingested without discrimination. @0 Chlorella was the dominant item in the food. Other algae constituted a small fraction. The ingested food also contained a large amount of debris. 3) Except for the diatoms and fragments of green filamentous algae, most of the ingested algae passed out undigested. 4) Experiments showed that starved tadpoles fed on filaments of Spirogyra and the cells of these were partly digested in the alimentary canal.Item Responses of freshwater animals to sodium cyanide solutions III. tadpoles of Rana temporaria(University of Peradeniya. Peradeniya, 1965) Costa, H.H.Experiments with tadpoles of Rana temporaria with sodium cyanide solutions gave generally similar results to those with fish and Gammarus. Tadpoles, however, are less sensitive than than fish but more sensitive than gammarus. The response limit for frog tadpoles is about 0.00001N. Changes of temperature, pH and dissoved oxygen had effects on their reactions similar to those seen with fishes and GammarusItem Responses of freshwater animals to sodium cyanide solutions II. Gammarus pulex(University of Peradeniya. Peradeniya, 1965) Costa, H.H.Experiments with Gammarus puler with cyanide solutions gave generally similar results to those given by experiments with fish. These animals however, appeared to be less sensitive than fish. The response limit for Gammarus, for sodium cyanide, is about 0.0001N. Addition of thiosulphate to sodium cyanide reduce the toxicity but unlike with fish, the reactions are accelerated. Increasing the temperature, increasing or decreasing the pH and lowering the oxygen content had effects on their reactions similar to those seen in fishesItem Responses of freshwater animals to sodium cyanide solutions. I. fish(University of Peradeniya. Peradeniya, 1965) Costa, H.H.The present work includes the results of several hundred experiments to test the reaction of fish to sodium cyanide solutions using an which is a modification of that used by Jones (1947b)Item The development of buds on the rhizome of Polypodium vulgare L.(University of Peradeniya. Peradeniya, 1964) Dissanayake, M.D.1) The origin bud in Polypodium vulgare L. is traced to detached moristems seperating laterally from the apical meristem. 2) These meristems normally develop into recognizable buds when some distance away from the apical meristem, but on the destruction of the apical meristem buds were formed at the points of origin of the detached meristems. 3) When the apical cell group was lighly punctured, buds, and in some instances leaves, had their inception at the ventral half of the apical meristem. 4) The buds are in vascular connection with the axis from their inception.Item The Pteridophytes of the Knuckles region(University of Peradeniya. Peradeniya, 1964) Abeywickrama, B.A.Item Observation on the structure and life-cycle of the digenetic fish-trematode Transversotrema patialense (Soparkar)(University of Peradeniya. Peradeniya, 1964) Crusz, H.; Ratnayake, W.E.; Sathananthan, A.H.Progenetic, egg-laden metacercariae of the trematode Transversotrema patialense (Soparkae, 1924) (Digenea: Transversotrematidae) have been recovered from under the scales of the freshwater fish Ophicephalus bloch and Macopodus cupanus (Cuv. et Val.) Caught in Batalagoda, Ceylon. The fish O. punctatus , M. cuponus and Tilapia mossambica (Peters) have been infected in the laboratory with the cercariae of this trematode, emitted by snails of the species Melanoids tuberculata (Muller). Many of the mrtacercariae that developed under the scales of these fish had ripe eggs. Uninfested, laboratory-bred snails of the same species became infested with radiae and cercariae of T. patialense, after exposure to fish carrying the matacercariae. At no stage were the metacercariae found to be eneysted. The mature metacercariae has been more precisely observed and described.Item The digestive enzymes in the alimentary system of Acrotelsa collaris (Thysanura:Lepismatidae)(University of Peradeniya. Peradeniya, 1964) Modder, W.W.D.Item A new species of Paratelphusa milne-edwards (Crustacea ; Brachyura) from Ceylon(University of Peradeniya. Peradeniya, 1961) Fernando, C.H.