No. 26.] ARTHROSTRACA OF CONNECTICUT. 



97 



Stout and longer than first pair; last two joints of peduncle sub- 

 equal ; flagellum about as long as peduncle and composed of about 

 fifteen segments. 



Mandibles large but quite short ; principal cutting edge divided 

 into three or four teeth ; secondary cutting edge likewise denticu- 

 lated ; molar tubercle large and close to cutting edge ; palp well 

 developed, triarticulate with last joint longer than second and 

 provided with long setse near the slightly pointed tip. Lower 

 lip broad, with outer plates evenly rounded and with mandibular 

 processes short and broad ; inner plates small. First maxillae 

 with inner plate broad and rounded, with six plumose spines on 

 inner margin ; outer plate with very oblique distal margin armed 

 with three strong teeth and inner margin with short setse distally ; 

 palp strong, made up of two joints of which the distal one is more 

 than twice as long as the proximal one and armed at its rounded 

 apex with seta. Second maxillse with outer plate curved and 

 rounded apically, inner plate broader than outer one and tapering 

 to a rounded apex ; outer plate with setse apically ; inner plate 

 with setse at apex and on inner margin. Maxillipeds with very 

 large palp ; inner plate small, rectangular, not reaching as far as 

 first joint of palp; outer plate with rounded apex, bearing short 

 setse on inner and apical margins ; second joint of palp very long, 

 with abundant setse on inner margin, third joint about half as 

 long as first and second together and with setse at apex, fourth 

 joint about half as long as third, slightly tapering and provided 

 distally with a spine tooth. 



First gnathopods stouter than second pair; basal joint broad, 

 with setse on posterior margin toward distal end ; carpus tri- 

 angular with setse on short, rounded posterior margin ; propodus 

 longer than basal joint, with very oblique palm extending nearly 

 to base of joint and armed with a double row of strong, blunt 

 spine teeth, many of which bear a notch and a cilium near apex ; 

 dactyl very long and curved. Second gnathopods with basal 

 joints more slender than that of first pair; merus with posterior 

 margin very convex and with a fascicle of setse ; carpus longer 

 than in first pair with numerous fascicles of spines on hind 

 margin ; propodus broadly oval, with palm straight and not very 

 oblique and provided with a double row of spine teeth as in first 

 pair. First two pairs of pereiopods slender. Third, fourth, and 

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