Description of a new Genus of Amphipod Crustacea 1 ). 



Batea, nov. gen. 



Hit Tafel XXV. 



Antennae simple. Coxae of the first pair of gnathopoda rudimentary, those 

 of the second pair of gnathopoda and the first two pair of pereiopoda largely 

 developed. Coxae of the second pair of pereiopoda deeply excavated upon the 

 upper part of the posterior margin. First pair of gnathopoda rudimentary, con- 

 sisting of coxa and basis only; second pair of gnathopoda subchelate. Mandibles 

 having an articulated appendage. Maxillipeds having a squamiform plate on both 

 the basis and ischium joints. Fourth and fifth pairs of pleopoda with styliform 

 rami, sixth pair with subfoliaceous rami. Telson single, deeply cleft. 



Species Batea catharinensis, F. M. 



I will here add some remarks on the sexual differences of this interesting 

 species. The pereion is somewhat longer and higher in the female; the antennas 

 of the same are shorter. The first joint of the peduncle of the upper antennae has 

 three, the second four fasciculi of hairs on the inferior side in the male ; they are 

 wanting in the female. The long setae at the extremity of the alternate articles 

 of the flagellum of the first antennae are directed downwards in the female, back- 

 wards in the male. The third and fourth joints of the peduncle of the lower an- 

 tennae have fasciculi of short hairs on their upper sides in the male, which are 

 wanting in the female. (The eyes are larger in the male.) The flagellum of the 

 lower antennae has long upward-directed setae at the extremities of alternate joints 

 in the female, which do not exist in the male. The first pair of gnathopoda are 

 shorter in the male, with but few hairs near the top ; they are as long as the basis 

 of the second pair of gnathopoda in the female, slender, flexible, with long hairs 

 on the anterior margin, and shorter curved hairs at the distal extremity. The coxae 

 of the second pair of gnathopoda are much higher in the female. The first two 



i) Annals and Magazine of natural History 1865. p. 276 277. Plate X. 



