OVARIAN STRUCTURE AND ROLE OF NUCLEOLAR EMISSIONS IN VITELLOGENESIS OF THYROPYGUS NIGROLABIATUS (NEWPORT)
S. BlSWAS *
DEPARTMENT OF ZOOLOGY, PANJAB UNIVERSITY, CHANDGARH-160014, INDIA.
M. L. SAREEN *
DEPARTMENT OF ZOOLOGY, PANJAB UNIVERSITY, CHANDGARH-160014, INDIA.
AMANJIT GILL *
DEPARTMENT OF ZOOLOGY, PANJAB UNIVERSITY, CHANDGARH-160014, INDIA.
*Author to whom correspondence should be addressed.
Abstract
Role of nucleolus in vitellogenesis of a millipede, Thyropygus nigrolabiatas has been studied histomorphologically and histochemically. Nucleolar emissions are budded from the nucleolus and are then pushed into the ooplasm, little later than their disappearence protein yolk develops. These emissions are completely acidophil before their disappearence. The amphinucleolus itself after the process of nucleolar emissions has ceased becomes completely oxyphil and prominent vacuoles appear in it. The yolk spheres first appear when the oocyte measures about 0.83 mm, while the fully developed ovum (about 1.8 mm diameter) is laid with thick chorion.