lyOPODS OF NORTH AMERICA. 7l 



the terniiiiiil ahdoiniiial segment, and arching over the telson. Inner 

 branch with posterior margin widely rounded and extending beyond 

 telson. Both branches have the margins smooth, entire. 



First gnathopods \yii\\ small hand. Dactyl us short. Free imier 

 margin of propodus furnished with hairs. Second gnathopods and 

 first periopods similar in shape to, but smaller in size than tirst pair 

 of gnathopods. The free inner margin of the propodus is beset with 

 two spines, the carpus with one spine. The remaining periopods 

 have a single spine at the distal margin of the propodus and two 

 spines on the carpus. 



One specimen, a female, was coliected by Prof. A. K. Verrill at the 

 Bermudas in 11>()1. 



Type in Peabody Museum of Yale University. C'at. No. 3.349. 



This species differs from ^1. dofi</ata Norman, in the shape of the 

 outer branch of the uropoda; in the length of l)oth branches, as com- 

 pared with the terminal al)dominal segment, and in the fact that the 

 margins of the outer bi'anch in this species ar(> smooth and not cren- 

 ulate, as in ^1. ehm<i(it(i. 



16. Genus CALATHURA Norman and Stebbing.« 



Abdomen short with the segments not very distinctl}' defined in the 

 male, but distinct in the female. Both pairs of antenna' in both sexes 

 with nudti-articulate fiagella. Buccal mass projecting, cone-shaped. 

 Anterior lip terminating in an obtusely conical point. Posterior lip 

 slightly bifid at the tip. Anterior maxilhv simple, spear-like; termi- 

 nal part armed with recurved teeth. iNIaxillipeds with the basal part 

 narrow, oblong; palp composed of three articles; epignath small, 

 rounded. JNIandibles terminating in an acutely-pointed lancet-like 

 organ. 



ANALYTICAL KEY TO THE SPECIES OF THE GENUS CALATHURA. 



a. Eyes not conspicuous. First pair of antenna' with flagelluin twelve jointed, not 

 lonjier than the lenojth of the head. Second pair of antenn;p with tiie tlageUuni 

 twelve jointed. First three segments of thorax bounded laterally by carina. 

 Terminal segment of body triangular, acute at apex, margin not crenulate. 

 Superior or outer branch of uropoda oval in form, sliglitly dentated. Inner 

 branch acutely triangular Vnhdlmra hrandnnta (Stimpson) 



a'. Eyes conspicuous. First pair of antenine with Hagellum seventeen jointed, more 

 than twice as long as the length of the head. Second pair of antennae with the 

 flagellum twenty-three jointed. First three segments of thorax not bounded 

 laterally by carina'. Terminal segment of body linguate, rounded posteriorly, 

 with crenulate margin. Superior or outer branch of the uropoda narrow, elon- 

 gated, not dentated. Inner branch rounded. 



Calaihura crenulata Richardson 



"See Sars, Crust, of Norway, II, 1899, pp. 44-45, and Norman and Stebbing, 

 Trans. Zool. Soc. Lond., XII, 1886, Pt. 4, p. 122, for characters of genus. 



