ON MORPHOLOGY AND MORPHOGENESIS OF URONYCHIA SETIGERA DURING ASEXUAL DIVISION

Using protargol technique the morphogenesis of a marine ciliate, Uronychia setigera during its asexual division has been studied. The main process is: 1) the opisthe's oral primordium appears de novo under the pellical posterior to the buccal field, from which the AZM1, AZM2, PM and one of the frontal cirri will be derived;The proter's oral primordium appears (under the pellical, too) anterior to the parent AZM2, from which membraneds 7-11 of AZM1, the whole AZM2, PM and one of the frontal cirri will be originated, 2) Two groups of FVT-cirrus anlagen each with 5 streaks occur de novo, it will be differentiated separately to the formula of 3:3: 2: 2: 3,which will be developed to the frontal, ventral and transverse cirri in both dividing parts. Different from that of most other hypotichs, the process of development of the cirral anlagen according to an order from left to right 3) The numbers of the FC,VC,TC, LMC are steady for 4, 2, 5, 3; 4) The lst frontal cirrus comes from PM anlagen;5) Anlagen of dorsal kineties (DK) appear within the old structure; caudal cirri come from the right-most two anlagen: the lst one comes from the DK5,whereas the 2nd and the 3rd one derive from the DK6.