Il8 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



Mandibles without palp. First maxillae with inner plate 

 slender and tipped apically with two plumose setse; palp uni- 

 articulate, small. 



Second gnathopods in the male either feebly chelate or more 

 usually strongly subchelate; in the female either feebly chelate 

 or subchelate. 



Third uropods usually with a single ramus. Telson usually 

 short. 



Orchestia Leach. 



First pair of coxal plates small ; fifth pair almost as deep as 

 the preceding and deeply bilobed. 



First antennae very small, much shorter than peduncle of 

 second which is elongated and subpediform and has the first two 

 joints coalesced with the head and not provided with a gland cone. 



Mandibles without palp. First maxillae with only a slight 

 rudiment of a palp. Maxillipeds with the triarticulate palp 

 short and broad. 



First gnathopods small, subchelate in both sexes, the pro- 

 podus with a distinctly defined palm. Second gnathopods very 

 dissimilar in the two sexes ; in female feeble, with an imperfectly 

 chelate propodus and rudimentary dactyl ; in male very strongly 

 developed, with subchelate propodus. 



Terminal uropods with a single minute ramus. Telson short, 

 thick, and broad, rounded at the-tip. 



Orchestia agilis Smith. 



1874. Orchestia agilis, Smith, Rep. Com. Fish, for 1871-2, 

 p. 555, pi. 4, fig. 14. 



Eyes large. 



First antennae very short, not reaching as far as penultimate 

 joint of peduncle of second pair; flagellum shorter than peduncle 

 and made up of three or four segments. Second antennae less 

 than half as long as body; peduncle stouter in male than in 

 female with last joint slightly longer than preceding; flagellum 

 shorter than peduncle and made up of ten or fifteen short 

 segments. 



First pair of coxal plates higher than long and considerably 

 smaller than second pair. 



