AMPHTPODA OF SOUTHERN NEW ENGLAND. 



501 



length of carpus, subquadrate in outline; palms somewhat oblique ami uneven, sharply marked off 

 from the posterior margin, armed with a stout spine near middle and a large spine followed by several 

 smaller ones near distal end; in the female the gnathopods are smaller than in the male and mure 

 nearly equal in size and shape; in the first pair the hand is not so narrow as in the male; hand of 

 second pair resembles in shape that of male, palm less oblique than in first gnathopods; postero-lateral 

 angles of second and third abdominal segments produced and acute, the margin above the angles gen- 

 erally furnished with short seta^; the three posterior segments with a median projection bearing a 

 fascicle of spinules and a lateral fascicle <>n either side; last pair of uropods with both rami stout, inner 

 nearly as long as first joint of outer; inner margin armed with about four stout spines; outer margin 

 of outer uropods armed with about six groups of stout spines; telson with a group of two or three 

 spines near base and three on apical margin, with another spine near the latter close to outer margin. 



Color, olive brown to reddish brown, the margins of the segments colored a little more deeply than 

 the other parts. Above the liases of the pleopods and first pair of uropods is a red, orange, or pink 

 spot, produced by an aggregation of globules. Some of the globules are highly colored, while others 

 are nearly or quite colorless. There is usually also a long patch of colored globules along the intestine. 



Length, about 25 mm. Arctic specimens, according to Sars, attain a length of 48 mm. 



Gammarus locusta. male. Woods Hole, Mu>s. 



The distribution of this species is very extensive, reaching throughout practically the whole of the 

 circum-boreal region. On the eastern side of the Atlantic it extends into the Mediterranean Sea, and 

 on the western side all along the New England coast and probably considerably further south. In 

 the Pacific Ocean it extends from Bering Strait down the coasts, both of Asia ami North America, 

 for a considerable distance. This is the species of amphipod decidedly most often met with in collec- 

 tions from New England. It is abundant near the shore, but ranges into a depth of over 50 fathoms. 



Gammarus annulatus Smith. 

 Gammarus naiator Smith, Kept. (' s Fish Com. Is71-J, p. 558. 



Eyes more or less reniform, broader than in locueta; antennfe often not more than one-third the 

 length of body; first pair shorter than second, with second joint of peduncle only a little shorter than 

 first and the third half the length of second; secondary flagellum nearly half the length of primary, 

 peduncle of the second antennae longer than flagellum, the last joint a little longer than preceding 

 one; both pairs of antenna- with very long, fine, plumose hairs; first four pairs of coxal plates very 

 deep, the lower margins of anterior three fringed with long hairs; first gnathopods in the male with 

 hand narrowly oval, palm uneven, very oblique and continuous with posterior margin of hand, armed 

 near the center with a stout spine, a pair of stout spines near distal end, above which is a double row 

 of smaller blunt spines; hand of second gnathopods of male oblong, broader than that of first pair, 

 with palm less oblique, concave in the center where the large spine is situated, and armed with a 

 double row of spines at the distal end, the two rows being unequal in size and in number of spines; 

 in the female the hands of both gnathopods are less stout than in the male, and are nearly equal in 



