HIGHER CRUSTACEA OE NEW YORK CITY 1 59 



poda rather large and subchelate. Terminal nropoda slightly larger 

 than preceding, and with rami fringed with hairs and spines. 



Fig. 27 Calliopius laeviusculus (After Sars) 



Found, according to Smith, in tidal pools and among algae. 

 Length 10-14 mm. Color light green, whiter dorsally. 

 Taken at South Beach, S. I. 



Family gammaridae 

 Antennulae and antennae long and slender, the former with an 

 accessory appendage. Mandibles with a palp. Gnathopoda large 

 and subchelate, generally stronger in the male. Pereiopoda more 

 or less slender, the three posterior pairs gradually increasing in 

 length. Terminal uropoda generally projecting beyond the others, 

 biramous and with the rami more or less foliaceous. Telson small 

 and more or less deeply cleft. 



Gammarus locusta (Linn.) 



Cancer locusta Linnaeus. Fauna Suecica. ed.2. p. 497. 

 Gammarus locusta DeKay. /. c. 1844. p. 37. Sars. /. c. 1895. p-499, 

 pi. 176. 



Antennulae longer than antennae and with flagellum of latter 

 shorter than peduncle. Gnathopoda small and equal in size. Pere- 

 iopoda with stiff spines. Last three segments of abdomen with 

 median and lateral fascicles of spines. Third abdominal segment 

 produced. Terminal uropoda with rami subequal and fringed with 

 hairs and spines. 



This is a littoral form and is the commonest of our Amphipoda, 

 being found all along the shores of the bays, under stones which 

 are covered at high water. It is not at all at home on land, but, 



