184 



BULLETIN 15 8, UNITED STATES NATIONAL MUSEUM 



Color. — Body semitransparent, washed with a faint tinge of 

 creamy yellow, and with transverse bands of reddish brown on the 

 dorsal surface arranged as follows : One over the mouth shorter than 

 the others; one on the first and one on the second thoracic segment, 

 reaching almost to the lateral margins; one on each side of the 

 fifth segment but not meeting on the midline; much wider bands 

 covering the posterior half of the first and second abdominal seg- 

 ments and extending entirely around the body; these bands are 

 wider on the sides and narrow on the dorsal and ventral surfaces. On 

 the ventral surface also the various appendages are outlined in light 



brown and the grooves be- 

 hind the first and second 

 legs are dark reddish 

 brown. The eggs are 

 creamy yellow, with red- 

 dish centers; no eye is visi- 

 ble. 



Female. — Body somewhat 

 depressed, the e p i m e r a 1 

 plates of the metasome 

 rather prominent and an- 

 gular at their posterior 

 corners; fifth segment much 

 narrower than the fourth; 

 caudal rami considerably 

 wider than long; urosome 

 segments with smooth pos- 

 terior margins. First an- 

 tennae 9-segmented, the 

 distal portion (last 5 seg- 

 ments) about one-third as 

 long as the proximal part; 

 hand of maxilliped chela stout and without a spiniform process; exo- 

 pod of first legs tipped with three subequal denticulate claws, with a 

 long slender seta at the inner corner, and a much shorter one at the 

 outer corner. Inner expansion of basal segment of fifth legs with 

 four denticulate setae, the inner one not reduced in size, distal seg- 

 ment oblong, its outer margin with a continuous fringe of cilia, its 

 inner margin with scattered hairs. Total length, 0.5-0.66 mm. 



Male.—^\\gh.t\y larger than the female ; hand of chela on first an- 

 tennae ovoid, only moderately swollen, with a simple dactylus. 

 Exopod of third leg curved strongly inward, its basal segment a 

 little longer than the second segment, the distal segment oblique 

 at its tij), its spines wide, but relatively very short, the seta at the 



Figure 124. — Harpacticus gracilis: a. Female, dor- 

 sal (after Sars) ; 6, female, fifth leg; c, male, 

 fifth leg ; d, male, maxilliped 



