392 



PART II. SYSTEMATIC ACCOUNT 



a 



D ? 





Fig. 155. Zenkevitchiana longissima: A - spermatophore ; В - anterior membranous part of the tube; 

 С - middle part of the tube ; D - hind part of the tube. (After Ivanov, 1957л.) 



whole tube, with the exception of the hindmost part, is segmented. The 

 boundaries between the rather long segments are detectable only by careful 

 inspection and look like clean superficial formations, or narrow belts, covered 

 with transverse lines (Fig. 155C). The front end of the tube is transparent, 

 limp and delicate, but the segmentation is visible here also (Fig. 1555). At 

 the hind end the tube gradually becomes much more stiff and brown, while 

 the hindmost end of all is dirty-grey with the firmest walls (Fig. 155/)). The 

 tube may be up to 150 cm long and the anterior membranous part up to 

 15 cm. The diameter of the front end may reach 1-6 mm, but is more often 

 c. 1-0 mm; the diameter near the hind end is c. 04 mm. 



Material : a great many tubes, some with animals and some empty. 



Locality: Kuril Trench. 



Depth: 4840-9950 m. 



