Volume 98, Issue 3
May 1989, pages 149-222
pp 149-166 May 1989
InChaerephon plicata the definitive amnion is formed by the development of folds. The yolk-sac splanchnopleure undergoes progressive collapse and folding until it ultimately remains as a free gland-like structure with hypertrophied endodermal and mesodermal cells. It acts as an active haemophagous organ after limb-bud stage. An extensive chorio-vitelline placenta, which is formed during early gestation is progressively abolished and replaced by the chorio-allantoic placenta. Two kinds of chorio-allantoic placenta are formed—a diffuse endotheliochorial placenta, which persists until about midpregnancy, and a definitive discoid placenta which is mesometrically located, labyrinthine and haemomonochorial.
pp 167-173 May 1989
Histological profile of the anterior and posterior lobes of the principal salivary and accessory glands of the reduviidAcanthaspis pedestris Stal. has been discussed in relation to enzyme pattern of the posterior lobe and the zootoxic substances of the anterior lobe as well as the protein fractions of the salivary gland lobes and the haemolymph.
pp 175-179 May 1989
The freshwater diaptomid,Heliodiaptomus viduus was subjected to biochemical analysis to study its sex-related differences. Its chemical composition was similar to that of other copepods, the concentration of the components decreased in the order of protein > lipid > carbohydrate. The ovigerous females show higher dry weight and consequently the protein, lipid and carbohydrate concentrations are greater than non-ovigerous females and males. There are also considerable qualitative and quantitative differences in the free amino acid composition.
pp 181-186 May 1989
Energy budgets of the solitary egg parasitoids,Anastatus ramakrishnae (Mani) andTrissolcus sp., and a gregarious egg parasitoid,Xenoencyrtus sp. nearniger Riek on the eggs ofHomoeocerus prominulus have been compared. Energy allocation for consumption, assimilation and metabolism were greater in the gregarious parasitoid than in the solitary parasitoids; on the other hand, higher production efficiency and lower assimilation efficiency were noticed in the solitary parasitoids than in the gregarious parasitoids. The rate of consumption, assimilation, production and metabolism of gregarious and solitary parasitoids have been compared in the light of their reproductive efficiencies.
pp 187-191 May 1989
The temporal pattern of accumulation of glycerol was examined during the early diapause period in silkworm eggs. Studies on the activities of two important enzymes viz. NADP-dependent glycerol dehydrogenase and NADP-dependent glycerol phosphate dehydrogenase showed that the latter may be more important than the former in the production of glycerol during diapause in silkworm eggs.
pp 193-197 May 1989
Topical and oral application of penfluron toPapilio demoleus Linn indicated that 7·6 μg of penfluron was needed through topical method to produce 50% mortality. Penfluron treatment caused a marked reduction in growth to a significant level of 42% in oral administration at dose 1·96 μg and 35% in topical application at sublethal dose 1·52 μg over that of control larva. The efficiency ofPapilio demoleus to grow on citrus plant was very much affected.
pp 199-209 May 1989
The present study deals with the awakening and roosting behaviour of mynas. In the annual cycle of these mynas, 3 distinct phases were noticed—the pre-breeding season (November–March), breeding season (April–July) and post-breeding season (August–October). The various roosting activities of mynas such as the time of waking up and calls, the time of arrival and departure of the first bird and up to the last bird, communal noise and the time of final settlement at the communal roost show a systematic diurnal and seasonal changes in relation to the times of sunset and sunrise (i.e. the light and dark periods of a 24h day). These changes were found to be consistent at all the roosts under observations and during all the years of the study. These changes seem to be governed by endogenous rhythms, which are slightly altered due to the endocrine secretions particularly in the breeding season and are also modified due to the adverse climatic conditions.
pp 211-222 May 1989
Population density, composition, age structure and fecundity ofMoina micrura have been studied in a eutrophic pond. The average clutch size of this species ranged from 1–4·4 eggs. The relationship between mean brood size and body length has been established. The volume of parthenogenetic eggs of this cladoceran ranges between 0·2 and 0·9 million μ3 and the adaptive significance of this has been discussed. The mean instantaneous birth rate which preceded maximum density of population resulted in a value of more than one.