i82 DISCOVERY REPORTS 



region. The notopods begin at the third segment and the neuropods at the fifth. 

 Bristles smooth; hooks in single rows throughout the body. 



Two pairs of branchiae T. cincinnatus 



Three pairs of branchiae ... T. setosus 



Thelepus setosus (Quatrefages). 



Fauvel, 1927, p. 273, figs. 95 a-h. 



Thelepus plagiostoma, Hessle {nee Schmarda), 1917, p. 214. 



Occurrence. St. WS 234 (i); WS 247 (i juv.); WS 583 (i); WS 742 (4 juv.); WS 755 (3); 

 WS 784 (2); WS 787 (i); WS 804 (i); WS 811 (4); WS 869 (4 with tubes). 



Specific characters. Three pairs of gills. Dorsal bristles on the first 30-60 

 chaetigers. About 20 more or less distinct gland-shields. Nephridia in segments 4-7. 

 Abdominal region long, narrow and twisted. Towards the end of the body the uncini- 

 gerous tori form projecting, rectangular pinnules. 



Thelepus cincinnatus (Fabricius). 



Hessle, 1917, p. 212. 



Fauvel, 1927, p. 271, figs. 95 i-m. 



Occurrence. St. 371 (numerous); WS 33 (2); WS 225 (2); WS 246 (4); WS 248 (2); WS 785 

 (i); WS 801 (i); WS 803 (i); WS 804 (8); WS 871 (numerous). 



Specific characters. Two pairs of gills. Eye-spots many and conspicuous. Dorsal 

 bristles sometimes continued almost to the end of the body. Ventral gland-shields 

 indistinct. Nephridia in segments 4-7. In the abdomen the uncinigerous tori are 

 gradually transformed into projecting rectangular pinnules. 



Genus Streblosoma, Sars 

 Dorsal bristles over a large number of segments. Two or three pairs of branchiae, 

 each branchia consisting of several simple filiform filaments, not as a rule arising from 

 a common base. Dorsal bristles smooth and capillary. They begin at the second seg- 

 ment. The hooks begin at the fifth segment (4th chaetiger). They are in single rows 

 throughout the body. 



Streblosoma bairdi (Malmgren) var. antarctica, var.nov. (Fig. 32 a-f). 



Occurrence. St. WS 33 (2). 



Specific characters. Of these specimens one is slightly larger than the other and 

 measures 30 mm. by 2 mm. for about 55 chaetigers. They have 28 and 26 pairs of noto- 

 pods respectively. Eye-spots are not visible. The buccal segment forms a swollen 

 underlip. The ventral surface is glandular over about the first 20 chaetigers, but the 

 glands are more highly developed over the first 10. Three pairs of gills composed of one 

 or two simple filaments. Nephridial papillae not visible. Dorsal bristles capillary, of 

 two kinds : (i) a longer kind with a narrow smooth border (Fig. 32 a) ; (2) a shorter kind 

 apparently without a border (Fig. 32 b). The hooks begin at the 4th chaetiger and in the 

 anterior region have a transverse row of two to three teeth (Fig. 32 c, d) above the main 



