368 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxm. 



tracery of transparent dots or points which are scattered over their 

 dorsal surface. These dots are circular in outline, sharply defined, of a 

 light yellowish color, and transparent, thus showing prominently 

 against the dark-brown background of the general surface. They 

 are not arranged in any definite pattern, differing in different indi- 

 riduals, but they are approximately symmetrical in the two plates 

 of any specimen. 



Genital segment much larger than the carapace, elliptical or 

 spindle shaped, tapering considerably toward either end; posterior 

 sinus two-fifths of the entire length, narrow and slit-like, and enlarged 

 but little at the base; posterior lobes closely appressed but not over- 

 lapping ; sixth segment lobe small and entirely concealed between the 

 genital segment and abdomen, but plainly visible on the ventral sur- 

 face after removing the abdomen. 



Abdomen transversely elliptical, one-half wider than long, with 

 evenly curved margins. On either side of the anterior margin is a 

 small rounded knob which projects forward beneath the genital 

 segment. Anal laminae large, each one as long as the abdomen and 

 half as wide, tipped with three rudimentary setaa at the center of the 

 terminal margin, two small spines near the outer corner and one near 

 the inner one. 



First antennae slender and not prominent; second pair stout with a 

 long terminal claw which is strongly curved. First pair of adhesion 

 pads ovate and small; second pair angular and still smaller; on each 

 half of the apron of the third legs two of the pads are in close contact 

 near the lateral margin, while the third one is removed some little 

 distance from them toward the median line. Mouth tube relatively 

 short and slender; second maxillaj boot-shaped and relatively large, 

 their bases far forward in front of the base of the mouth tube. First 

 maxillipeds slender, terminal joint longer than the basal, both claws 

 with a fringe of setae. Second maxillipeds with a strongly swollen 

 basal joint and a stout terminal claw, which shuts dowTi against two 

 large corrugated knobs. 



The spines on the rami of the swimming legs are short and stout 

 with toothed margins, while the setae are all rudimentary, except 

 those at the tip of the endopod of the second legs. The arrangement 

 is as follows: First exopod 0, I; 4, III: endopod 0, 0; 5, III: second 

 exopod 0, 0; 1, I; 7, III: endopod 0, I; 5, III: third exopod 1,1; 

 1, I; 5, II: endopod 1, 0; 3, II: fourth exopod 3, VII: endopod 

 0, IV. 



In the fourth leg joints the rami are fused indistinguishably, but 

 the spines are scattered along the margin in such a way as to indicate 

 that the ramus is a fusion and not a single joint, a fact still further 

 attested in the endopod by indentations on the margin. Of the 

 genital organs the oviducts are coiled once in each half of the genital 



