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This paper compares the species richnesses, Bray-Curtis similarities, species diversities, evennesses, and the results of various analyses (multivariate, logarithmic series, and lognormal distribution analyses) of insects from four orders (viz., Hemiptera, Orthoptera, aculeate Hymenoptera, and Coleoptera) inhabiting a medicinal plant, Calotropis procera among eight sites within industrial and nonindustrial zones in the Purba Medinipur district (erstwhile Midnapore), West Bengal, India. Both cluster analysis and principal component analysis indicate an effect of industrialization on the diversity of the four insect orders. The species community at each site exhibits an almost pure lognormal distribution. Bootstrap estimation of species diversity also points to the effect of industrialization. A comparison of the values of x and N/S of the logarithmic series indicates a typical relationship between the species community and its diversity. The number of unique species among the eight study sites is 6 according to jackknife estimation. Beta-diversity analysis of the samples shows the impact of industrialization on the abundances and species richness of the insects. Altogether, 16 types of analytical procedure are applied for this purpose, and their suitabilities for this kind of data set are assessed. Disturbance, probably due to industrial emissions, has changed the compositions and structures of the insect communities out to a distance of at least 6 km from the core industrial area.

Macrochlamys indica is a hermaphrodite terrestrial pulmonate mollusk. Transmission electron microscope studies were done on the ovotestis of young and adult (older) M. indica which are elaborated in this paper.The ovotestis contains numerous lobes each of which contains many ovoid shaped acini which are occupied by stages of spermatogenesis and a single oocyte. In younger snails, the acini contain stages of developing spermatogenesis, whereas each acinus of older snails is composed of single large oocyte and few stags of spermatogenesis. The number of Sertoli cells is high in the acini of younger snails than in older snails. Details of the cellular organization of the Sertoli cell are described. Some long thin threads extend from the acinar boundary to acinar lumen. The anterior end of these threads is either free or directly connected to the developing cells of spermatogenesis. There are two types of cells in the interacinar space of the ovotestis in both younger and older snails. One cell is small oval interstitial cell and other is thin elongated periacinar cell. The acinar boundary contains secretory cells with deeply stained nucleus. In the acinus of older snails, the Sertoli cells do not form any barrier between oocyte and spermatogenic cells.Functions of the periacinar cell and interacinar cell are discussed. It is found that the spermatogenesis is highly active in younger snails with single dormant oocyte while process of oogenesis predominates in the older snails. The reproductive strategy of this pulmonate species thus depends on the individual's body size and their maturity.

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The snake shed skin has long been used in folk as ethnomedicine for the treatment of various therapeutic purposes. The present study investigates the effects of the shed skin aqueous extract (SSAE) of the nonpoisonous snake Ptyas mucosus on the development of the ovotestis of the hermaphrodite slug, Onchidium tigrinum. The ovotestis consists of numerous ovoid-shaped acini, include both spermatogenesis and oogenesis. It is observed that the nonpoisonous SSAE has some significant detrimental effects on the gametogenesis of the slug only on direct contact into the body fluid of the individuals, otherwise, the SSAE has no significant harmful effect on the ovotestis constituents. The most noticeable pathological effects in spermatogenesis are - the arrangement of developing sperm bundles and their typical twisting pattern have deteriorated, the head of the sperm become a small bead-like structure, the pyramidal development of the spermatogenic cells is lower in number in the acini. On the other hand, the oocyte lost its basal integrity with the acinar boundary. The oolemma of the oocytes becomes irregularly shrank. Some small ooplasmic blebbing have commonly been found near the oolemma. The cell membrane of most of the cells in the acini has been damaged and several bare nuclei have frequently been observed in the acinar space. The somatic cells such as Sertoli cells, follicle cells, etc. in the acini appeared as the cellular remnants. It advocates that the SSAE has more detrimental effects on the oogenic cells than that of the spermatogenic cells in the mollusc.