20 GO. Sårs. 



ing, as a rule, laterally. They are claviforrn in shape, with 

 the outer pigmented part, or the eye-ball, evenly rounded 

 off. Between them, in the middle of the front, the simple 

 eye, or ocellus, is distinctly observable as a small dark spot. 



The antennulæ (ibid ) are rather elongated, fully attaining 

 the length of the head, and are very delicate, filiform, in the 

 living animal being extended in front, and somewhat divergent. 



The antenna?, as usual, are very different in the two 

 sexes. In the female (see figs. 1 and 3) they have the character 

 of 2 simple, oblong oval blades hanging down from the head, 

 and each terminating in a short, somewhat recurved point. 

 They seem to be quite immovable, and have the edges densely 

 clothed in their outer part with delicate sensory hairs. 



In the male these antennæ are greatly developed, and 

 of a very peculiar structure (see figs. 2, 4, 5). When fully 

 extended, they equal in leDgth the whole anterior division 

 of the body; but, as a rule, they are folded in beneath the 

 head, forming a sharp sigmoid curve (see fig. 2). They 

 each consist of a thick cylindrical basal part and a very 

 flexible terminal part of more than thrice the length of the 

 former. The basal part is very muscular, and is armed 

 at the end outside with a strongly chitinized slender claw 

 curving inwards. The terminal part is narrow cylindric in 

 form, and of a very soft consistency, with numerous trans- 

 verse folds. It exhibits in the middle an abrupt, almost 

 genicular bend, its distal part being doubled upon the 

 proximal part, and somewhat beyond this bend it carries 

 below a number of irregular tentacular papillæ. At the 

 end it expands to a hand-like dilatation defined from the 

 cylindrical part by a well-marked constriction, and prolonged 

 into 2 narrow digitiform processes, which cross each other 

 at the base (see figs. 5 and 6). This apical part of the 



