278 



DISCOVERY REPORTS 



two points, the anterior one larger than the other; a prominent rounded knob projecting 

 between the "eyes", hollow beneath, and arching over the bases of ist antennae; a 

 distinct though shallow neck behind the "eyes"; free margin of the head costate, the 

 costa more prominent on the postero-inferior margin, and on the anterior margin of 

 the larger projecting point and the lower margin of the frontal knob. 



The surface of the "eyes" is shagreened like the rest of the body, and no trace of 

 ocelli or facets is visible. The front portion of the ocular lobes is dull reddish-brown, 

 darker in colour than the rest of head (cf. coloured reproduction of sketch taken from 

 life). 



Fig. 163. Pegohyperia princeps, Brnrd. «, b. Two views of left mandible (palp omitted in b). c. Maxilla 2' 

 d, e. Two views of maxilla 1, with distal margin of palp further enlarged. /. Maxilliped, with apex of outer 

 plate further enlarged. 



Peraeon segments subequal, each with a transverse dorsal and dorso-la'teral shallow 

 groove and raised rounded ridge; on segment 1 the ridge precedes the groove, on the 

 other segments the groove is in front of the ridge, which is specially prominent on seg- 

 ments 5-7; the dorsal profile is therefore undulate. Postero-inferior angles on all seg- 

 ments rounded ; antero-inferior angles on segment 1 slightly, on segments 6 and 7 more 

 prominently produced forwards, but not acute. Side-plates 1 and 2 shallow, slightly 

 produced forwards as rounded lobes, both with a horizontal keel above and overhanging 

 the insertions of the gnathopods. Side-plates 3-5 considerably deeper, 3 projecting 

 outwards, 3 and 4 quadrangular, 5 triangular. Side-plates 6 and 7 shallow. 



Pleon broad, not abruptly narrower than peraeon, dorsal profile undulating; pleural 



