Zandt and in August, 1953^ we also hatched larvae of this type, and pre- 

 sumably A. vistulensis Siwak and observed a number of subsequent stages 

 of their development. 



The development of the 

 eggs of Ancylodiscoides takes place 

 in from 3 to 6 days depending upon 

 temperature. The larva which has 

 just emerged from the egg (Fig. 171) 

 is of the same shape and structure 

 in all species as the larvae of 

 Dactylogyrus, but differs in the fact 

 that its attaching armature (Fig. 172) 

 has two middle hooks in addition to 

 the edge hooks (14 and not 12 as 

 Siwak erroneously indicates). The 

 Fig. 170. Ancylodiscoides siluri latter are incepted above the edge 



(Zandt), middle hooks of the disc hooks in the shape of chitinous 



of the adult worm from the gills little parentheses just as takes place 



of Silurus glanis L. from the anaong Anchyrocephalus (s^. lat. ) 



Delta of the Volga. cruciatus Wedl. but in opposition to 



the latter, the connecting plate of 

 this pair is as yet absent, it is incepted later. 



p. 160 



Fig. 171. Ancylodiscoides sp. sp. free-swimjning larvae, A- -A. 

 vistulensis (Siwak), the larva is enlarged 400 times (According to Siwak, 

 1932); B--A. siluri (Zandt); C--A. strelkowi Ackmerow. 



172 



