4 HYPERIIILE. 



whole of this division of Amphipod Crustacea. The 

 walking legs are nearly of similar length, but have the 

 coxae, especially of the two anterior pairs, not so deep 

 as in the Gammarina, and the thighs less broadly de- 

 veloped. The natatory appendages possess no con- 

 spicuous distinction from other Amphipoda, but the three 

 caudal pairs have the peduncles broad and flat, and the 

 rami sharp and triangular. The middle piece is small, 

 triangular, and squamiform. 



The geographical distribution of this genus appears 

 to be world-wide, since it has been observed in the 

 Atlantic as well as the Indian and Pacific Oceans, from 

 the arctic to the tropical latitudes. 



