274 



PART II. SYSTEMATIC ACCOUNT 



"5. debile is distinct from all other species of Siboglinum in the lack of 

 ornamentation of the tube, but otherwise belongs to the group of small 

 species with one row of pinnules on the tentacle. These are : S. cinctutum 

 Ivanov, S. frenigerum Ivanov, S. caulleryi Ivanov, S. pusillum Ivanov, S. 

 buccelliferwn Ivanov and S. weberi Caullery. The striated bridle is similar to 

 those of S. minutum Ivanov and S. tenne Ivanov, but other characters do 

 not agree. 



Fig. C133. Siboglinum debile: А, В - anterior end of animal, ventral and dorsal views; С - girdle. 

 (After Southward, 1961b.) 



"It is possible that these unringed tubes are merely the anterior ends of 

 some more normal tubes, but the sample in which they occur contains a 

 large number of specimens of different species in various tubes, and none of 

 the animals are like those described above as S. debile." 



Material : 20 fragments of tube, eight occupied. 



Locality: Java Sea: Siboga Station 212 (5°54'S 120°19'E). 



Depth: 462 m.] 



