Volume 94, Issue 4
August 1985, pages 359-441
pp 359-375 August 1985
This review of the air-breathing fishes deals with morphology, histochemical analyses of respiratory membrane and muscles, morphometrics and development of respiratory organs, hematology and other blood parameters, oxygen uptake by gills and skin, physiological and behavioural aspects, ecology and effects of pollutants on the morphology and behaviour. The scientific significance and application of the studies of functional morphology and physiology in understanding the alteration caused by pollutants have also been elucidated.
pp 377-381 August 1985
Food habits, parasites and length-weight relationship in the hill-stream fishLabeo dyocheilus were examined. The frequency distribution of the pseudophyllidean cestode,Bothriocephalus teleostei in this fish has been reported to be log-normal.
pp 383-387 August 1985
A comparative study of the pH of crystalline style, digestive diverticula and stomach fluid in six bivalve species,Anadara rhombea, Crassostrea madrasensis, Meretrix meretrix, M. casta, Katelysia opima andDonax cuneatus revealed that the digestive diverticula are more acidic while crystalline style is either slightly acidic or nearly neutral. The significance of this finding is discussed. In vitro dissolution of crystalline style of all the six species in buffer solutions of varying pH from 3·6 to 9·0 was observed and the study indicated that the optimum pH for style dissolution is around 8·0 in all species exceptingDonax cuneatus where some dissolution was recorded only at pH 9·0. Based on the physical changes observed in the style, a mechanism of style dissolution has been put forward.
pp 389-398 August 1985
The freshwater catfishMystus punctatus was successfully bred in the laboratory by injecting the pituitary extract of the marine catfishTachysurus macuiatus. The number of eggs released by a single female fish was 9050 ± 700, the relative fecundity was 43·1 and the fertilization success was 85 ± 2·8 per cent. The average diameter of the unfertilized eggs ranged from 1·27 to 1·35 mm and the fertilized eggs ranged from 1·45 to 1·50 mm. The eggs hatched within 18 to 24 hr at a water temperature of 28·5 ± 1·8°C, and the percentage of hatching was 78%. The larvae metamorphosed into juveniles within fifteen days of their hatching. A description of the egg and larval development to metamorphosis is given.
pp 399-406 August 1985
The results of our studies on the Brazilian family Serritermitidae are presented here. Microsculpturing is simple and consists of a few rows of small, tongue-shaped papillae on the anterior and posterior wing margins and a few rows of angular arrowheads in the anterior one-third of the wings. Hairs are almost absent, a few small ones being scattered on some of the veins. The bearing of wing microsculpturing on the phylogeny of the Serritermitidae is discussed. It is concluded that the family arose as a lone sideline from the common ancient rhinotermitid stock. The other line from this stock gave rise to the Stylotermitidae on the one hand and the Rhinotermitidae on the other.
pp 407-411 August 1985
Changes in protein concentration due to electrical stimulation have been investigated at different time intervals in cockroach ventral nerve cord. Significant increase in total protein concentration was observed at 15 min interval of stimulation. Increase in protein concentration was also observed in ventral nerve cords incubated with exogenous glucose. Microdisc Polyacrylamide gel electrophoresis at 15 min interval has revealed an increase in low molecular weight protein fractions in nerve cords from stimulated group. The data clearly depict the changes in protein due to electrical stimulation stress.
pp 413-419 August 1985
Middle and posterior parts of the silk gland of fifth instar bivoltine and multivoltine races ofBombyx mori and their hybrid were analysed for the concentration of fibroin, DNA, RNA and total protein. Fibroin content of the silk gland increased rapidly from the beginning of fifth instar upto the spinning stage. Concentration of DNA in the middle silk gland was maximum at 24 hr and decreased thereafter. In the posterior silk gland, the concentration of DNA increased upto 72 hr and then decreased, RNA concentration was maximum at 72 hr and 120 hr, in the middle and posterior silk gland respectively. The total protein content increased gradually upto the spinning stage in the middle silk gland whereas it increased upto 120 hr and decreased sharply thereafter in the posterior silk gland. The difference in the concentration of these constituents in the silk gland was correlated with the differential silk output in both the pure races and their hybrid.
pp 421-426 August 1985
The chronomorphological events during the development of the egg of the freshwater caridean prawn,Macrobrachium nobilii, were followed from spawning to hatching. The female is receptive only for a 30-minute period after the premating moult. After mating, spawning ensued within 9 ± 3 hours and was completed within 15–20 seconds. Unmated females also spawned but the eggs did not survive. The rate of egg development increased 2·5x for a temperature rise of 10°C. Hatching was synchronised underin vitro conditions indicating uniform development of a clutch.
pp 427-433 August 1985
The accessory glands of reproduction in slender loris exhibit reduction in secretory activity following castration for 15 days and 30 days. Administration of androgens (testosterone—propionate and 5α dihydrotestosterone) to castrated animals had a differential effect in maintaining the biochemical parameters like citric acid and fructose.
pp 435-441 August 1985
Succession and assemblage of the round-head borers infestingCanarium euphyllum Kurz have been described. The borer pests have been categorized into two major groups. The first group includes the borers of standing trees and freshly felled logs, while the second constitutes the species infesting the dead logs after some seasoning. Even among the borers belonging to each of these groups, there is a clear sequence of succession of species infesting the logs depending upon the period lapse after felling and subsequent conditions of the host.