474 



BULLETIN (>K THE BUREAU OF FISHERIES. 



three times as deep as wide, convex in front and concave behind; fourth pair markedly deeper than 

 wide; first gnathopods with hand narrow, distally tapering, somewhat curved backward and about 

 two-thirds length of carpus; palm pectinate with fine spines and not clearly defined above; dactyl 

 about half length of palm; second gnathopods with hand longer than broad, densely ciliated and not 

 exceeding half length of carpus; first and second perseopods with merus produced below nearly to 

 middle i if carpus; dactyl fully two-thirds lengthen' narrow and somewhat incurved propodus; poste- 

 rior margin of basal joint of last perseopods with large, acute serrations; serrations on basal joints of 

 third and fourth perseopods very much smaller; dorsal margin of third abdominal segment quite sud- 



Hippomedon srrrattts, female. Newport, R. I. The second antennae were broken in the specimen drawn. 



denly deflected near posterior end; postero-lateral angles of this segment strongly produced and 

 upturned much as in //. propinquus Sara. ; fourth abdominal segment with a dorsal carina; last uropods 

 projecting beyond first pair, rami about twice length of peduncle; telson cleft to beyond middle, the 

 lobes pointed. 



In the male the first antennae are a little longer and have more numerous joints than in the female, 

 and the second antennae are nearly as long as the body. 



Length, 12 mm. 



Newport, R. I. Off Cape Ann, 36 feet. 



This species differs from //. denticulatus in the broader and much less abruptly upturned process 

 at the postero-lateral angles of the third abdominal segment. From //. propinquus and //. holboUi it 

 differs in having a larger lobe on the first basal joint of the first antenna' and in the form of the hand 

 of the first gnathopods. In both these species the hand is widest near the middle and strongly convex 

 behind; in our species the hand tapers from the base and is slightly concave behind. Serraius differs 

 from all three of the species mentioned in having coarser serrations on the 

 posterior margin of the basal joint of the last pair of pereeopods. 



Hoplonyx cicada Fabricius. 



Hoplonyx cicada. Angle 

 nl third abdominal 

 segment and tels-.n. 



Eyes narrow above, the lower part dilated; lateral corners of head rounded; 

 first antenna? about as long as head and first two thoracic segments, secondary 

 rlagellmn nearly as lung as primary one and composed of about seven joints; 

 second antennae much longer than first; first four coxal plates more than twice 

 as deep as their segments; fifth pair nearly as deep as wide; first gnathopods 

 slender, the ischium twice as long as wide; propodus as long as carpus, scarcely tapering distally; palm 

 oblique; second gnathopods with propodus oblong, about half as long as carpus; postero-lateral angles 

 of third abdominal segment produced into a small tooth; fourth abdominal segment with only a slight 

 dorsal depression; telson nearly twice as lo'Dg as wide, tapering somewhat distally, and cleft nearly to 

 the base, a minute spinule at tip of each lobe. 



