Volume 88, Issue 4
August 1979, pages 241-310
pp 241-256 August 1979
The structure and biomass ofPoecilocerus pictus population in four fields in Bangalore were estimated by direct observation method. Results on the density ofP. pictus, the survivorship curve of the grasshopper and the growth of the population are reported.
The data on feeding rates, assimilation and conversion obtained in the laboratory were applied to the size and structure of theP. pictus populations in the different fields to estimate the rate and efficiency of energy flow through the population. The results indicate the defensive mechanism developed by the plant against predation. Efficiencies of exploitation, assimilation and production by the populations averaged 3·4, 34 and 15% respectively. Factors like predation, food and space do not appear to regulate the size of the population. Probably it is controlled by intrinsic population factors.
pp 257-264 August 1979
Moulting in isopod crustaceans occurs in two phases and the moulting of posterior half precedes the anterior. But in the present study observations were made onSphaeroma walkeri in which during moulting the cuticle in the anterior half is cast off first followed by the posterior half.
pp 265-268 August 1979
A new histozoic myxosporidian,Kudoa sphyraeni n.sp., infecting the muscles of the gut ofSphyraena jello Cuv. (Fam: Sphyraenidae) is described.
pp 269-272 August 1979
A new species of myxosporidian,Myxosoma lairdi n.sp. infecting the gut ofLiza macrolepis Smith is described.
pp 273-276 August 1979
An attempt was made to screen out some promising varieties of sorghum resistant toSitophilus oryzae Linn. The studies revealed that varietal reaction in regard to number of weevils emerged was significant. Hybrids CSH-8R, CSH-1 and CSH-5 and varieties, 168 and 370 showed least population of weevil than local R-16 and 604. The developmental period of the weevil showed no significant differences. The results obtained in respect of the number of females emerged were significant while the reverse was the case with the number of males emerged. An overall higher percentage of females was observed in majority of the varieties tested. Local varieties R-16 and 370 favoured development of females. Varieties 604 and 370 had maximum percentage of infested grains and also recorded maximum weight loss than hybrids. The resistance rated was CSH-8R>168>CSH-1>CSH-5>370>R-16>604 taking weevil emergence as a criterion.
pp 277-285 August 1979
In the crabMenippe rumphii, embedded in the connective tissue of the oesophagus there are salivary or oesophageal glands. Each gland is made up of four to eight conical cells with a central cavity. Histochemical observations on the gland cells have shown the presence of some neutral and weakly acidic sulfated mucopolysaccharides. The glands are positive to toluidine blue showing gamma metachromasia. Similar type of glands are also observed in the walls of the hindgut. The cytochemical details of the gland cells have been discussed in detail.
pp 287-297 August 1979
The embryo ofHipposideros speoris enters the uterus at the morula stage of development. The blastocyst implants superficially and circumferentially and the embryonic mass is so oriented during implantation that it faces between the antimesometrial and the lateral sides of the uterus. The most conspicuous progestational change in the uterus concerns the uterine glands which undergo hypertrophy and become wide thereby reducing the endometrial stroma to thin strands. During implantation the glands undergo destruction, accompanied by the destruction of endometrial cells, and the formation of symplasma. The trophoblast on the embryonic hemisphere is more invasive than that in the other regions of the blastocyst.
pp 299-304 August 1979
Two new species,D. guptai andD. ramamensis, belonging to thehistrio group of subgenusDrosophila of the genusDrosophila are described from Darjeeling, India. Their taxonomic relationships, based on the morphology and male genital structures, are established.
pp 305-310 August 1979
Two new speciesCleaveius leiognathi andC. port-blairensis from the marine fishes of Goa, Andaman and Nicobar Islands have been described in this paper. The two species differ from each other and from the only already described species of the genus in the number and size of proboscis hooks.