176 DISCOVERY REPORTS 



53° 3°' 15" S., 63 ' 29' W. Thus, the species may be said to belong to the shallower waters of the 

 Sub-Antarctic zone. | 



It seems probable that, as Ohlin suggested, this species is identical with Idothea miersi Studer 

 (1884), which was collected in the same locality (47° i' 6" S., 63° 29' 6" W.). 



Text-fig. 14. Pseudidothea bonnieri. (a) Antenna, x 16. (6) Flagellum of antennule, x 60. (c) Cutting edge of left mandible, 

 X 30. (d) Right mandible, x 30. (e) Right antennule, x 30. (/) Coxae of first and second pereiopods, x 32. 



Pseudidothea scutatus sp.n. (Text-figs. 15, 16) 



Microarcturus scutatus Stephensen, 1947, pp. 15-17, text-figs. 5 and 6. 



Occurrence. St. 170: 23. ii. 27, 61° 25' 30" S., 53° 46' 00" W., 342 m., 4 $? (breeding), 2 SS, 3 immature. 



A male and a female specimen from St. 170 are chosen as holotypes. 



Description. The largest male of the Discovery collections was damaged so that measurements 

 cannot be given, the smaller one is 19 mm. in length and 6 mm. in greatest breadth; the breeding 

 female is considerably broader and measures 23-5 mm. in length and 875 mm. in greatest breadth. 



The body is subcylindrical, scarcely depressed (Text-fig. 15a) and characteristically sculptured; all 

 the specimens were thickly coated with fine mud, etc. The anterior margin of the head is deeply 

 excavate, and a median narrow groove extends backwards to unite with the transverse groove which 

 separates the head from the first pereion somite with which it is fused. The eyes, which are small and 

 dorso-lateral in position, are slightly raised. Between the eyes are two raised areas separated from 

 each other by the median groove; immediately behind these, in the mid-line, is a small rounded 

 tubercle. On the first pereion somite, behind the groove separating it from the head, is the first pair 

 of a series of large dorsal protuberances, the flattened surfaces of which are raised i mm. above the 



