ANCE1JS HALIDAII. 



203 



I SO POD A. 



ABERRANTIA. 



ANCEUS HALIDAII. 



Specific character. Male, with the cephalon nearly square, the lateral 

 anterior angles truncated for the insertion of the antennae, middle of the fore 

 margin produced into three broad divisions, of which the central is slightly 

 porrected ; margin finely serrated ; antero-dorsal surface of cephalon very 

 broadly concave ; mandibles small, scarcely half the length of the cephalon, 

 entire on the outer margin ; second pair of gnathopoda composed of five broad 

 joints. Male exserted organ rather short and thick ; pereiopoda with small 

 spines on the terminal joints. 



Female, with the outer gnathopoda five-jointed, narrower than in the 

 male ; inner gnathopoda wanting ? 



Length, one quarter of an inch. 



Anceus formica? HESSE, Me'm. $trang. Acad. Sci. t. xviii. p. 39, pi. iii. 



figs. 5, 6, 7. 



THIS species is at once distinguished from A. maxil- 

 laris by the very different structure and small size of 

 the mandibles and foot-jaws in the males, and by the 

 latter character as well as the (apparent) want of the 

 inner pair of foot-jaws in the females. The head of 



