PA RASITIC COPE PODS— 1 VILSON. 475 



laminae, destitute of plumose setae; those of the first two pairs are 

 two-jointed, while the third and fourth pairs show })ut a single joint. 

 The spines are arranged as follows: First exopod, 1, 3, endopod, 

 0, 0; second exopod, 0, 4, endopofl, 0, 1; third exopod, 3, endopod, 

 0; fourth exopod, 6, endopod, 0. Of the reproductive organs the 

 oviducts are coiled very tightly and in hopeless confusion in either 

 half of the genital segment. In general the coils are narrower and 

 more tightly woinid in the anterior portion of the segment. The 

 final coils are in the shape of a large S on either side of, and close to, 

 the median line, the openings to the exterior being just in front of 

 the base of the abdomen. 



The cement glands are narrow and very long, and are bent into a 

 sickle shape, the curve reaching backward on either side beneath the 

 ventral lobe of the abdomen. The semen receptacle could not be 

 distinguished with sufficient clearness to determine its exact shape, 

 but it is situated in the usual position, just in front of the l)ase of 

 the abdomen. The spermatophores are ellipsoidal, twice as long as 

 wide, and curved like a couple of parentheses marks; the ducts lead- 

 ing from them cross in the usual manner, and each empties into the 

 vagina on the opposite side of the body. This genus, therefore, is 

 unlike Cecrops in that the organs witliin the genital segment extend 

 far behind the base of the abdomen; there is thus no (k^ubt that the 

 abdomen is fastened to the ventral surface of the genital segment 

 and is not terminal. The certainty in this case increases the proba- 

 bility in the case of Cecrops, where it is not easy to decide. 



Total length, 20 mm.; length of carapace on mid-line, 5.34 mm.; 

 width of same, 7.1 mm.; length of fourth segment plates, 5.56 mm.; 

 of genital segment plates, 8.35 mm. ; width of latter, 9.5 mm. 



Color a uniform light yellow without any pigment markings; the 

 claws and chitin ribs which strengthen the carapace are darkened to a 

 brownish hue. 



Male. — Carapace similar to that of the female, but relatively a little 

 shorter and wider; grooving on the dorsal surface indistinct; e^^-es 

 invisible in the adult; no teeth along the lateral margins of the cara- 

 pace. Fourth segment plates nearly circular, their combined area 

 considerably less than the carapace, but covering more than half of 

 the genital segment plates; their posterior margins are thickly set 

 with teeth. They project forward at the anterior corners in a broad 

 and rounded shoulder on either side. 



Genital segment small, two-thirds the size of the carapace, or])icu- 

 lar in outline and strongly flattened dorso-vcntrally, its dorsal plates 

 fused along the mid-line for their anterior half, but separated for 

 their posterior half, the posterior margins thickly set with teeth. 

 Abdomen very small and weak, subquadrangular, fastened to the 

 ventral surface of the genital segment so that its posterior margin 



