OLIGOBRACHIA DOGIELI 



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one end, while from the other springs out a long thread, at whose base the 

 delicate membrane of the spermatophore forms a pair of wing-like expan- 

 sions. The proximal part of the thread is comparatively stout for a significant 

 length, then the thread gradually diminishes in thickness, passing into a 

 delicate long distal part. 



Fig. 91. Oligobrachia dogieli: Spermatophore. 

 (After Ivanov, 1957a.) 



Fig. 92 Oligobrachia dogieli: Tube: A - middle 

 part; В - anterior part. (After Ivanov, 1957a.) 



The ringed tube (Fig. 92) is very firm but elastic, and dark-brown in 

 colour. The length of the equal regular brown rings is about one-half to two- 

 thirds of the diameter of the tube and they are separated by narrow trans- 

 parent spaces. Both the rings and the spaces are transversely folded and 

 wrinkled. Towards the front end of the tube the rings gradually become paler 

 and finally vanish, so that the anterior extremity is membranous, very delicate, 



