No. 26.] ARTHROSTRACA OF CONNECTICUT. 207 



ovate, obtuse; inner with margin straight and outer margin 

 curved and emarginate near the tip. Both rami and posterior 

 portion of telson cihated. 



Length 50 mm. 



Distribution: between delta of the Mississippi and Cedar 

 Keys, Florida ; of? Marthas Vineyard ; Fishers Island Sound ; 

 Gulf of Maine; Gloucester, Massachusetts; Nova Scotia; Labra- 

 dor; Newfoundland; Gulf of St. Lawrence; Greenland; Hudson 

 Bay ; Ireland ; Iceland ; North Sea ; in the German Sea ; Spitz- 

 bergen. 



This species is parasitic on skates, cod, an4 halibut. 



CYMOTHOID^. 



Antennse strongly reduced and without clear distinction be- 

 tween peduncle and flagellum. 



Mandibles with palp. First maxillae with a single lobe con- 

 sisting of a single joint furnished with four spines at the tip. 

 Second maxillae bilobed at the tip and provided with numerous 

 spines. Maxillipeds with two-jointed palp, the terminal joint of 

 which is furnished with hooks. 



Coxal plates distinct on all the segments except the first. Legs 

 all prehensile, terminating in strong hooked dactyls. 



Telson and uropods usually not ciliated. 



Parasitic in habit. 



.ffigathoa oculata (Say). 



1818. Cyniothoa oculata^ Say, Jour. Acad. Nat. Sci. Phila., 

 vol. I, p. 398. 



1880. Mgathoa loliginea, Harger, Rep. U. S. Com. Fish, for 

 1878, p. 393, pi. 10, fig. 66. 



Body elongate oval in outline, nearly four times as long as 

 broad, slightly dilated just posterior to the middle. Head broadly 

 rounded in front, as broad as long, and with posterior margin 

 produced in three equal shallow lobes. Eyes large, compound, 

 covering nearly half the area of head above, situated on postero- 

 lateral angles of head. 



First antennse as long as head, composed of eight segments 

 and separated at base ; first segment short and stout ; succeeding 

 two a little longer but scarcely distinguishable from the five 



