156 Annals <>f the South African Museum. 



pleopods but not those of 3rd pleopods well developed, peduncles not 

 expanded ; 3rd uropod represented only by the lobe-like peduncle. 



This genus differs from the other genera of the family in having 

 long antennae, a palp on 1st maxilla and the peduncles of pleopods 

 not expanded. 



PLIOPLATEIA TRIQUETRA n. sp. 

 (Plate XXVI. Figs. 18-24.) 



Body about as broad as deep. Head short, rostrum upturned, with 

 a smaller tooth on either side. Eye round. A small tooth on the 

 anterior margin in front of eye, inferior margin keeled, ending in a 

 small tooth at the antero-latero angle. 



Peraeon segment 1 equal to head, segments 1-7 each surmounted 

 by a dorsal keel, strongest on 1st, where it is deeply bifid, on the other 

 segments it occupies only the posterior portions, a flat horizontal, 

 backwardly directed prominence 011 each segment just above the junc- 

 tions with the side-plates. Side-plates not contiguous, 1st nearly as 

 deep as its segment, subtriangular, widening below and projecting 

 forwards to antero-lateral angle of head, 2nd, 3rd, and 4th oblong, 

 not quite twice as deep as long and not as deep as segments, antero- 

 inferior angles of 1st to 4th rounded, inferior margin notched pos- 

 teriorly, postero-inferior angles subacute, 5th longer than deep, strongly 

 notched, anterior and posterior lobes acute, 6th and 7th similar to 

 5th but successively smaller. 



Pleon not strongly flexed, 1st and 2nd segments with a dorsal tooth 

 on posterior margin as large as that on 7th peraeoii segment, a small 

 subdorsal tooth on either side, 3rd segment smooth, unarmed except- 

 for the very obscure subdorsal teeth, 4th quite smooth, subequal to 

 3rd, postero-iuferior angles of 1st to 3rd segments obtusely rounded. 



Telson transverse, twice as wide as long, apical margin straight, 

 postero-lateral angles rounded. 



First antenna reaching to about 6th peraeon segment, 1st joint | 2nd, 

 upper apex of both 1st and 2nd joint projecting as an acute tooth, 

 lower margin of 1st with one subapical tooth, 3rd joint ^ 2nd, narrow 

 and unarmed, flagellum longer than peduncle, 15 jointed. 



Second antenna reaching to middle of flagellum of 1st antenna, 

 3rd joint short, 4th as long as broad, upper apex of both produced but 

 not prominently so, 5th equal to 3rd and 4th together, narrow and 

 unarmed, flagellum longer than peduncle, 11-jointed. 



Upper li[> entire. 



Lower lip, lobes broad, apically truncate, inner lobes absent. 



