nTrERin.T;, 2S7 



Division HYPERINA. 



The antennae are more or less abnormal. The maxillipeds are 

 imiicrlVctly developed, and cover the oral appendages as an imperfect 

 oporcidum. The gnathopoda arc generally small and loss powerful 

 than the pcreiopoda, and vary in the different families from (juite 

 simple to complexly clielate. The pereion has the segments separate, 

 or one or more fused together. The pleon has the appendages upon 

 the same typo as in the Gammarina, but their forms are more liable 

 to generic variation. 



This division is synonymous with Milne-Edwards's family of 

 HvpEuixis, and also with Dana's family of Hypeuidea. It contains 

 four families. 



Fam. 1. HYPERIDiE. 



The superior antenna) are formed with a distinct peduncle and fla- 

 gellum ; the fonuer consists of three joints, the latter is variable. The 

 inferior antennae consist of a peduncle and flagellum ; the peduncle 

 is five-jointed (?), the Hagellum multiarticulate. Gnathopoda more or 

 less complexly subchelate. Four anterior pairs of pcreiopoda sub- 

 equal, normal. Thi'ec anterior pairs of pleopoda normal ; three pos- 

 terior pairs broad, flat, and biramous. 



This family is remarkable for its thin integument and freedom 

 from hairs. 



1. LESTRIGONUS. 



Lestrigonus, Edwards, Ann. dcs Sc. Nat. xx. p. 392 ; Hist, des Crust. 

 iii. p. 81. 



Cephalon large, deeper than broad. Pereion short ; segments sub- 

 equal, three times as deep as long. Pleon longer than the pereion ; 

 first three segments long and deep ; fifth very short. Eyes large, 

 occupjrng the entire lateral walls of the cephalon. Antennae 

 longer than the cephalon, subequal, having articulate flagella. 

 Mandibles having an appendage. Gnathopoda completely sub- 

 chelate. Pcreiopoda cubequal. Pleopoda biramous. Telson 

 squamifonn, simple. 



1. Lestrigonus exulans. (Plate XLVIII. fig. 2.) P.M. 



Lestiigonus exulans, Kroyer, Gro/d. Amjlp. p. 68. f. 18. 

 Edwards, Hist, des Crust, iii. p. 82. 



Cephalon transversely ovate ; antero-inferior margin slightly ex- 

 cavated to receive the inferior antennae. Antenna) reaching to about 

 tlie third or fourth segment of the pereion : superior j)air having 

 the peduncle very short ; second and third joiaits shortor than the 



