WILSON, PARASITIC COPEPODS FROM JAPAN. 5 



The latter is elliptical, a little longer than wide, with 

 rather convex sides and very broadly rounded posterior lobes. 

 The posterior sinus is obliterated by the overJapping of the 

 posterior lobes. The egg strings are wide and about twice 

 the length of the body. 



The abdomen is one-jointed, triangulär, twice as wide 

 as long, and thoroughly fused with the anal laminae, the 

 only line of demarkation being the notches in the lateral 

 margins. The fifth legs are broadly conical and destitute 

 of spines or setae. 



The first antennae are two-jointed and sparsely armed 

 with setae. The terminal claw of the second pair is stout, 

 curved into the shape of a sickle, and armed with a long 

 row of large teeth. The largest basal one is double, the 

 others are single. The first maxilla is as wide as long, 

 strongly narrowed toward the tip, which is armed with a 

 long and stout spine having a swollen base. On the anterior 

 margin of the maxilla are two small spines and on the 

 posterior margin a minute process, tipped with a tiny spine. 



In the maxillipeds the pad is of medium size and ellip- 

 tical in outline, the terminal claw nearly straight and the 

 process opposite the claw nearly as long as the claw itself. 



In the swimming legs the rami of the first and second 

 pairs are two-jointed and armed with setae. The rami of 

 the third and fourth legs are one-jointed except the exopod 

 of the third pair, which is two-jointed; the endopods are 

 destitute of setae, the exopods are sparsely armed with them. 



Color (preserved material) a uniform yellowish white. 



Total length 6 mm. Carapace 2.40 mm. wide, 2.2 5 mm. 

 long. Genital segment 3 mm. wide, 3.2 5 mm. long. Egg 

 strings 12. 5o mm. long. 



{japonicus, belonging to Japan). 



Specific characters of young female. Carapace acorn- 

 shaped, nearly as wide as long, widest at the center, with 

 long and sharp lateral lobes and a wide reentrant median 

 lobe on the posterior margin. Frontal lobes indistinctly 

 separated from the carapace by grooves, their outer ends 

 very long and pointed. Second segment not yet fused with 

 the third, its lateral margins projecting and notched near 

 the anterior corner. Third and fourth segments each with 



