No. 26.] ARTHROSTRACA OF CONNECTICUT. 165 



First gnathopods short, with large carpus widening distally 

 and setose behind; propodus shorter than carpus, gently convex 

 in front, quadrately rounded behind, palm subequal to hind 

 margin; dactyl finely serrate. Second gnathopods in male very 

 large ; merus very small ; carpus elongated, produced beyond pro- 

 podus into a very large, acute process which has- a very large 

 tooth on its front margin ; propodus much narrower but not much 

 shorter than basal part of carpus, with a low elevation near 

 distal end of hind margin; dactyl with long setae apically. 

 Second gnathopods in female with carpus produced behind pro- 

 podus in a slender lobe which is armed distally with setae and 

 recurved spines ; propodus large, palm oblique and longer than 

 hind margin. 



First uropods projecting beyond second and third; peduncle 

 slender and much longer than rami; inner margin of peduncle 

 of second uropods with acute serrations; margins of rami of 

 second and third uropods acutely serrate, the serrations on inner 

 rami being the larger; third uropods with peduncle broad at 

 base and much longer than ramus which ends in two upturned 

 spines. 



Telson twice as broad as long, emarginate, with lobes armed 

 with numerous, very short, hook-like spines. 



Length 6 mm. 



Distribution; Europe, from Norway to the Adriatic; Rio 

 Janeiro; Bermuda; Vineyard Sound; Woods Hole, Massachu- 

 setts ; Great Egg Harbor, New Jersey ; Long Island Sound ; New 

 Haven (Smith), Noank, Connecticut, off Sea Flower Reef. 



The species occupies tubes which are affixed to hydroids.and 

 algae ; it is more common according to the Woods Hole Survey at 

 depths between 8 and i6 fathoms. 



Unciola Say. 



Body slender, depressed, with small angular, coxal plates. 



First antennae longer than second with an accessory flagellum. 

 Second antenna larger in male than female; flagellum multi- 

 articulate. 



Mandibular palps well developed, triarticulate. Maxillipeds 

 with outer plates short and broad and armed inside with strong 

 flattened spines. 



