94 DISCOVERY REPORTS 



The specimen recorded by Rustad was taken from water of a temperature of 0-55° C. and he states 

 that it can probably thrive in temperatures as low as 0-37° C. The Discovery material proves that his 

 surmise was correct, for the species was taken in waters ranging in temperature from over 6° C. at 

 station 226 down to — o-8° C. at station 162. 



Distribution. Off Kerguelen Island, 120 fm. ; South Georgia, 75 m. and 250 m. ; Cumberland Bay, 

 South Georgia, 140-0 m. ; South Shetlands, 785-810 m. 



Apart from Sars's original record from Kerguelen Island, until now this species has been recorded 

 only from off the north-east and north coasts of South Georgia. (Sars's specimen from the Antarctic 

 from 65 42' S., 79 49' S. was much larger and in all probability belonged to P. belgicae.) The present 

 records very considerably enlarge its known geographical range to the west in the South Atlantic. 



All the specimens referred to this species have been taken in depths of 75-320 m. except at station 

 J957 (785-810 m.). 



Pseudomma antarcticum Zimmer, 19 14 

 1914 Pseudomma antarcticum Zimmer, p. 389, figs. 



Occurrence : 



St. 182. 14. iii. 27 (day). Schollaert Channel, South Shetlands, 500-278 m., 1 adult $, 18 mm., 1 $ (damaged) 



and fragments. 

 St. 1957. 3. ii. 37 (day). South Shetlands, 785-810 m., 1 6*, 20 mm., 1 ovig. $, 21-5 m., 2 juv. 



Remarks. These specimens agree remarkably closely with the description and figures given by 

 Zimmer, the only difference being a slight variation in the shape of the anterior margin of the eye- 

 plates and in the number of serrulations on the antero-lateral borders. The anterior borders of the eye- 

 plate are not evenly arcuate, but show a slight concavity at about one-third of their length from the 

 median line. From the median cleft up to this concavity the margin is naked and onwards from it 

 the antero-lateral margins are armed with about 20-25 very fine serrulations. The long plumose setae 

 on the inner margins of the second and third segments of the antennular peduncles are particularly 

 noticeable. 



Distribution. The only previous record of this species is of the type from 65 15' S., 8o° o' E. 

 at a depth of 3425 m. The Discovery specimens were taken nearly as far south, but in much shallower 

 water, depth 278-500 m. 



Pseudomma belgicae (Hansen in MS.), Holt and Tattersall, 1906 



19066 Pseudomma belgicae Holt and Tattersall, p. 8. 

 1908 Pseudomma belgicae, Hansen, p. 12, figs. 

 1908 Pseudomma belgicae, Tattersall, p. 27, figs. 

 1913 Pseudomma belgicae, Hansen, p. 11, figs. 



Occurrence : 



St. 181. 13. iii. 27 (day). Schollaert Channel, Palmer Archipelago, 160-335 m., 4 imm. SS, 20-22 mm., 1 adult $ 

 with abdomen missing. 



St. 182. 14. iii. 27 (day). Schollaert Channel, Palmer Archipelago, 278-500 m., 1 S, 23-5 mm., 1 juv. ? and frag- 

 ments. 



St. 1644. 15. i. 36 (day). Bay of Whales, 626 m., 2 $$, 22-4 mm. 



Remarks. This species may be distinguished by the large ocular plate, which shows no trace of 

 serrulations and has only a small median cleft on the anterior margin, which is almost straight without 

 any kind of protuberances ; by the comparatively long antennal scale with its apex extending only 

 very slightly, if at all, beyond the particularly strong tooth which terminates the naked outer margin; 



