Browsing by Author "Supervised by Dr. Mohammad Nasim Siddiqi"

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    REPRODUCTIVE BIOLOGY OT BENSONIES JACQTIEMONTI (MARTENS 1869)
    (Department Of Zoology, University Of Peshawar, 1992-12) Rehana Parveen Aurangzeb M.Sc, M. Phill (Pesh); Supervised by Dr. Mohammad Nasim Siddiqi
    Bensonies jacquemonti is a medium sized terrestrial pulmonate snail which is commonly available at the campus of University of Peshawar, N.W.F.P., Pakistan. A detailed study of the reproductive activity, anatomy, histology and function of the different parts of the reproductive tract is worked out. There are two breeding seasons and theseare related to seasonal rainfall, temperature and humidity. The genital organs retain the basic pattern of stylommatophores. Different portions of reproductive tract assist in different processes of reproduction e.g. male tract helps in sperm movement in two ways, one, upward movement of home sperms to reach penial complex and second; downward movement of foreign sperms from bursa to reach fertilization pocket. Penial complex forms the spermatophore. The female tract secretes different nutritive and protective coverings for the egg. The dart stimulates the excitement for the copulation. Formation of spermatophore, role of bursa copulatrix, and mating behavior are observed. Premating behavior is very intricate and follows a complex courtship. Eggs are laid in egg chamber dug inside the soil. Developmental embryology from oviposition to hatching takes place 15-21 days, depending upon the temperature. In cold weather the incubation period is 18-21 while in summer it is 14-15 days. Post embryonic growth till maturity have been worked out.The effect of neurosecretory hormones on reproduction is demonstrated; it shows relation with cell differentiation. Optic tentacular hormone assists male sex cells while ablation of optic tentacles promotes oogenesis. During unfavourable condition they undergo dormancy, the process of under going dormancy and re-activation from dormancy has been observed to be the direct effect of the external factors.