毛尾刺虫无性生殖周期中的形态和形态发生

ON MORPHOLOGY AND MORPHOGENESIS OF URONYCHIA SETIGERA DURING ASEXUAL DIVISION

利用蛋白银染色法研究了毛尾刺虫的形态及无性生殖周期中的形态发生。其过程为：（1）后仔虫口原基出现在左缘棘毛内侧深层，其内的毛基体组装成整齐排列的小膜并分化成新AZM1，AZW2和口侧膜。（2）前仔虫口原基出现在老仔虫AZK2之前方深处，其随后发育成前仔虫的AZK2、口侧膜及AZM1的一部分，并更新老结构AZM1产的第7—11片小膜。（3）额腹横棘毛原基为5列，分别以3：3：2：2：3方式分化并最终产生前、后仔虫的恒为3、2、5根额、腹、横棘毛，另外3个毛基体被吸收。（4）第一根额棘毛于前、后仔虫的口侧膜原基产生。（5）背触毛6列，分别于前、后仔虫的中部范围产生前、后仔虫第1—6列新原基，每列原基向两端伸展替代老背触毛列，成为前、后仔虫相应的第1—6列新背触毛；三根尾棘毛在发生上分别来自于DK5和DK6。

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, AZK2, PM and one of the frontal cirri will be derived;The proter's oral primordium appears (under the pellical, too) anterior to the parent AZK2, from which membraneds 7-11 of AZM1, the whole AZK2, 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.