no. 3628 GENUS PARANTHESSIUS — HUMES 3 



Caudal ramus (fig. 7) elongated, 135m x 34m in greatest dimensions, 

 four times longer than wide. Outer lateral seta 52m, outermost terminal 

 seta 70m, innermost terminal seta 57/u. Two long median terminal 

 setae 195/x (outer) and 380m (inner) and inserted slightly dorsally. 

 Dorsal pedicellate seta small, 18ju long. All setae naked. Dorsal surface 

 of ramus without ornamentation. 



Dorsal surface of prosome and urosome with a few hairs (as in 

 fig. 1) ; ventral surface of urosome almost devoid of ornamentation. 

 Ratio of length of prosome to that of urosome 1.4:1. 



Egg sac unknown. 



Rostrum (figs. 8, 9) a rounded prominence with a rather blunt 

 posteroventral tip. 



First antenna (fig. 10) slender (about 358m in length) and 7-seg- 

 mented, with a sclerite on third segment (fig. 11) suggesting an 

 intercalary segment. Lengths of segments (measured along posterior 

 nonsetiferous margins) 13m (50m along anterior margin), 81m, 35m, 

 60m, 55m, 41m, and 36m respectively. Formula for armature, as in many 

 other lichomolgids, 4, 13, 6, 3, 4 + 1 aesthete, 2 + 1 aesthete, and 7+1 

 aesthete. All setae naked. 



Second antenna (fig. 12) 4-segmented. Armature 1, 1, 3, and 1,5. 

 All setae naked. Three long terminal setae on last segment jointed; 

 claw pale brown, 77m along its axis. Second segment with few short 

 spinules along outer edge. 



Labrum (figs. 13, 18) with two widely divergent posteroventral 

 lobes. 



Mandible (fig. 14) with a slender elongated blade bearing spinules 

 along each side. Paragnath (fig. 13) a small hairy lobe. First maxilla 

 (fig. 15) with four setae (in one first maxilla of one female only three, 

 seta nearest to two terminal ones being absent). Second maxilla (fig. 

 1 6) 2-segmented. First segment unornamented. Second segment having 

 on outer (ventral) margin a small proximal seta, bearing on inner 

 surface a seta with very short barbules and a long seta with spinules 

 along one edge, and terminating in a long lash with long spinules on 

 one margin and few small spinules on opposite side. Maxilliped (fig. 17) 

 3-segmented. First segment lacking spines or setae. Second segment 

 with two rather unequal setae. Small third segment terminating in a 

 spiniform process (not clearly articulated with segment) with a small 

 seta near base. Postero-outer surface of second segment and postero- 

 outer distal part of first segment with dense covering of fine short 

 hairlike ornamentation. 



Postoral area as in figure 18. Median region between mandibles, 

 paragnaths, and first maxillae slightly protuberant. A sclerotized line 

 between bases of maxillipeds. 



