POLYBRACHIA GORBUNOVI 



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The tentacular crown consists of 18 free tentacles disposed in a horse-shoe. 

 The fore-part of the body is a regular cylinder and the cephalic lobe a 

 triangle (Fig. 1605). The keels of the bridle, situated in the front half of the 

 fore-part of the body, are rather weakly developed, with tapered ventral ends 



Fig. 160. Polybrachia gorbunovi: A - front end of the body in ventral, and, В - in dorsal view; 

 С - non-metameric part of the metasoma in the zone of thickened papillae from the ventral side ; 

 D - tube. 



с - cephalic lobe;/- keels of the bridle; p - plaques; pa - papillae; s z - groove between the meso- 

 soma and the metasoma; sv - ventral sulcus; tc - tentacular crown. (After Ivanov, 1949.) 



