NO. 1580. NEW SPECIES OF CALIGIN.l^WILSON. 613 



Central portion of the carapace, including the cephalic and tho- 

 racic areas, strongly arched and raised considerably above the lat- 

 eral areas. To increase this difference the sides of the carapace are 

 folded over ventrally around the appendages as in Lernanfhropus. 

 Posterior sinuses broadly triangular and shallow; median lobe only 

 one-third the entire width and not projecting behind the lateral 

 lobes. Thoracic area the smallest yet observed in any of the Calig- 

 inse, only one-third the width and one-fourth the length of the cara- 

 pace; cephalic area correspondingly large. Free segment short and 

 less than one-third the width of the carapace, without plates or 

 processes. 



Genital segment the shape of an elongated acorn, not quite as 

 wdde as the carapace but longer, thus making its area about the 

 same. Its sides are evenly .curved and its posterior margin is 

 squarely truncated without lobes or processes. 



The abdomen is seven-eighths as long as the genital segment and 

 tw^o-jointed. The basal joint is elliptical, two-thirds as wide as the 

 genital segment, and more than four times as long as the terminal 

 joint, with evenly-curved sides. The terminal joint is less than half 

 the width of the l)asal, and carries a pair of small and widely sepa- 

 rated anal laminiB, each tipped with four short setiv. The egg 

 strings are the same wddth as the terminal abdomen joint and two- 

 thirds as long as the entire body; eggs comparatively large, 40 to 50 

 in each string. 



The first antennae are tw^o-jointed like those in Caligus and rela- 

 tively as large, but the second pair are rudimentary. They are 

 situated at the base of the rostrum, are three-jointed, the last joint 

 terminated by a minute claw , and the whole appendage is only half 

 the size of the terminal jomt of the first antennae. 



The fu'st maxilla? and furca are entirely lacking; the second max- 

 illee are reduced to mere points and are situated close to the sides 

 of the mouth tube at its base. They are so small as to be easily 

 overlooked. 



The mouth tube is short and w^ide, w-ith a framew^ork similar to 

 that in Lepeophtheirus hippoglossi. The mouth opening is terminal 

 and surrounded by a fringe of long hairs. The mandibles are 

 inclosed in the mouth tube and are of the same general shape as in 

 the other Caliginse, with teeth along both margins. 



The first maxillipeds are comparatively large and stout, and are 

 situated far forward, their bases anterior to the center of the mouth 

 tube and close to it. In fact, they occupy nearly the position usu- 

 ally taken by the second maxilla?. (See fig. 74.) 



The two joints are about the same length, the terminal one ending 

 in two claws, of which the inner is more than twice the length of 

 the outer. 



