4. DIPLOBRACHIA SOUTHWARDAE 381 



segments ; the new species is only about half the size of the smallest species 

 previously known. For the present it seems best not to propose a new generic 

 name for a species obviously closely related to Polybrachia. — E.C.S.] 



[Ivanov (in litteris) has moved this species to his subsequently everted 

 genus Diplobrachia — D.B.C.] 



D. capillaris has been collected at six stations, which are listed below : 



Depth 



Date Position (fm) No of specimens 



16. v. 58 47° 56' N 7° 57' W 340-350 1 empty tube 



16. v. 58 47° 50' N 7° 57' W 300-450 3 (and 1 empty) 



6. viii. 58 43°43'N 4°02'W 680-970 12 (and many empty) 



28. xi 58 48° 26' N 10° 08' W 730-780 2 (and 2 empty) 



30. xi. 58 48°39'N 9°50'W 750-850 2 



30. xi. 58 48°40'N 9°48'W 600-680 1 



[4. Diplobrachia southwardae sp. nov. Ivanov (Figs. D152-G152) 



An interesting new pogonophore was found in February, 1960, by R.V. 

 Vityaz? in the Arabian Sea east of the coast of southern India. Together with 

 Lamellisabella minuta sp. nov. (p. 436) and Siboglinum silone sp. nov., a 

 Sigsby trawl brought up, from a depth of 1300 m, many characteristic 

 segmented tubes containing a pogonophore with three or four tentacles. 

 When these were examined closely it was apparent that they belonged to an 

 undescribed species of the genus Diplobrachia, which, in honour of the 

 English student of pogonophores Dr. Eve C. Southward, I propose to name 

 Diplobrachia southwardae. 



The fore-part of the body is six to eight times as long as broad. The 

 very long cylindrical protosoma is divided from the mesosoma by a sharply 

 defined transverse groove lying a little in front of the bridle (Figs. *D\52A, B; 

 El 52 A). The very small rounded cephalic lobe is dorso-ventrally flattened 

 and partially enveloped the base of the tentacles. It is separated from the 

 main part of the protosoma by a post-tentacular groove (Fig. Е152Л, B). 

 Most of the individuals investigated had three tentacles, but one had four. 

 When three tentacles are present two are attached on the right side of the 

 protosoma and the third on the left (Figs. D 152$; Y.XS2A). In the individual 

 with four tentacles two appeared to be on the right and two on the left. The 

 tentacles are very long and have narrow bases. They are furnished with 

 pinnules arranged in a single row, in which, however, traces of an incipient 

 biserial arrangement can be detected (Fig. D152C). The pinnules are thick- 

 set and about 140/n long, but near the base of the tentacle they are shorter 

 and yet more thick-set. 



