i58 



DISCOVERY REPORTS 



Remarks. The colour appears to have been a uniform creamy white, the eyes pale 

 brown. This species would seem to be common in the deeper water area around the 

 Falkland Islands and between these and the mainland of South America. 



Distribution. Off Cape Virgins, 55-70 fathoms; west of Falkland Islands, 229 m. 



Chosroes decoratus, n.sp. (Fig. 92). 



Occurrence: St. 170. South Shetlands. 1 <J 20 mm., 1 ovig. ? 22 mm. 

 Description. Integument moderately indurated, with numerous minute ridge-like 

 granules causing a granulate appearance; these granules are arranged mostly trans- 

 versely, and are more distinct and prominent on the pleon segments, but extend also 

 over the 2nd joints of peraeopods 3-5. Head with short median point, ocular angles 



Fig. 92. Chosroes decoratus, n.sp. a. General view, sculpturing indicated on pleon segment 3. 

 b, c. Profile and frontal views of epistome and upper lip. d. Telson, with sculpturing indicated. 



rounded, post-antennal angles quadrate, hidden under 1st side-plates. Eyes large, sub- 

 rotund. Peraeon broadly rounded in anterior portion, the posterior margins of segments 

 1-4 slightly thickened; segments 5-7 with medio-dorsal keel, which is largest on seg- 

 ment 7, and on all three segments ends posteriorly in a forked tooth; postero-inferior 

 angles of segments 5-7 becoming increasingly prominent and produced; posterior 

 margins of segments 6 and 7 with a lateral tooth between the dorsal one and the 

 postero-inferior angle. Side-plates shallow, 1 and 2 rounded, 3 subquadrate, 4 trape- 

 zoidal, excavate behind, 5 and 6 with the anterior and posterior lobes subequal, 

 7 oblong. In the $ the lateral tooth on segment 6, the postero-inferior angles of seg- 

 ments 6 and 7 and the posterior angle of side-plate 7 are shortly bifid. 



Pleon segments 1-3 carinate, carina forming a forked tooth on segments 1 and 2, and 

 a simple tooth on segment 3 ; a lateral tooth on hind margin in segments 1 and 2 ; 

 postero-inferior angle of pleon segment 1 quadrate, of segments 2 and 3 produced in a 

 sharp point; segment 4 with a low rounded dorsal keel, which is notched below the 

 posterior apex; segments 5 and 6 smooth. There is also a slight lateral ridge or fold on 



