104 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 113 
backward from posterior side of a swelling in front of the produced 
angle of segments 5, 7, 9, 10, 12, 18, 15-17, and 18?. Last segment 
with apex narrowed and deflexed, surpassing the valves. Preanal 
scale truncate at apex. 
Gonopods with basal joint broad, flattened and with a smaller 
semiglobular second joint supporting a simple curved half-cylindrical 
blade. 
Enantiogonus fragilis, new species 
FIGuRE 5b-e 
Houotyre: Male, USNM myriapod collection 2644, Pifia area, 
Canal Zone, March 18, 1958, H. F. Loomis. 
Description: Body slender, 3.2 mm. long; color in alcohol light 
brown. 
Head with labrum scarcely indented at middle, sides straight, 
strongly oblique; front finely hispid; antennae rather slender with 
joints 2 to 6 subequal in length, jot 7 two-thirds as long as 6, joints 
2 to 4 equal in width, slightly exceeded by joint 5 with joint 6 a 
little thicker. 
Segment 1 narrower than segment 2, semicircular, the lateral 
angles sharply rounded. Ensuing segments with a transverse median 
impression; surface finely reticulated, raised into indistinct polygonal 
areas and with setae as mentioned for the genus. 
Segment 2 with outer margin of carinae rather broadly rounded 
and with two or three indefinite teeth (two on succeeding segments), 
posterior angle on each side slightly produced backward, posterior 
margin between the two angles triarcuate, becoming more noticeably 
so to about segment 11 or 12; posterior corners also more produced 
on succeeding segments to 17 where they reach their maximum size 
but are greatly reduced on segment 18 (fig. 5b). Pores large, defi- 
nitely dorsal, opening obliquely outward and backward from poste- 
rior side of a swelling in front of the produced corner. Last segment 
ending in a deflexed, truncate tip bearing four setae. Preanal scale 
broadly truncate at apex, the sides concave (fig. 5c). Legs with joint 
6 slender and nearly as long as joints 2 to 5 combined (fig. 5d). 
Gonopods as shown in figure 5e. 
Hypsiloporus, new genus 
Type sprEcies: Hypsiloporus proclivis, new species, by present 
designation and monotypy. 
Driacnosis: The shape of the body, segments and keels suggest 
Inodesmus Cook but the 20-segmented body and the dorsal setae in 
three rows, instead of scattered over the surface, immediately dis- 
tinguish this genus. 
