348 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



the peduncle, and consists of about ten to fourteen segments. The 

 maxillipeds (pi. V, fig. 28 &) have the external lamella (1) broader than in 

 the preceding species, with its inner margin straight and its outer mar- 

 gin curving pretty regularly to a slightly attenuated tip. 



The epirnera of the second, third, and fourth pairs are rounded behind, 

 and those of the last three pairs are less acute than in I. irrorata. 



Pleon ovate, a little constricted near the middle and pointed, its three 

 proximal segments rather less acute than in the preceding species. The 

 basal plate of the operculuin (pi. Y, fig. 28 e) tapers toward the end, and 

 the terminal plate is triangular, a little longer than broad. The stylet 

 on the second pair of pleopods in the male (pi. V, fig. 29 s and s') is slender, 

 nearly straight, surpasses the lamella to which it is attached, and is 

 obliquely truncate. 



Length 25 mm ; breadth 7 mm . The color is very varied, usually dark 

 green or brownish, with patches of yellow or whitish, transversely or 

 obliquely arranged. I have never observed a striped pattern of color- 

 ation, so common in I. irrorata, and it must occur very rarely if at all. 

 The color is usually darker than in that species. 



This species is found associated with the last among rocks and sea- 

 weed along the entire coast of New England! and extends northward 

 to Halifax!, Nova Scotia, and the Gulf of St. Lawrence!. It appears 

 to be a more northern species than I. irrorata, as it is comparatively 

 rare south of Cape Cod, while it is abundant in Casco Bay, Maine, and 

 in the Bay of Fundy. 



Specimens examined. 



