374 BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



FIG. 405. PENTIDOTEA WHITEI. x 



are nearly of equal length; the last one is clavate and somewhat longer 

 than either of the preceding ones. The first antennae do not extend 



beyond the second article of the peduncle 

 of the second pair of antennae. The sec- 

 ond pair of antennae have a peduncle com- 

 posed of five articles and a flagellum of 

 seventeen articles. The first article of 

 the peduncle is short, not reaching beyond 

 the basal article of the first pair of antennae ; 

 the next two articles are equal in length, 

 and each is twice as long as the first 

 article; the last two articles are each 

 nearly twice as long as the third article. 

 The maxillipeds have a palp of five 

 articles. 



The segments of the thorax are all of 

 equal length. The epimera of all the seg- 

 ments, from the second to the seventh, 

 inclusive, extend the entire length of the 

 lateral margin. The epimeron of the sec- 

 ond segment is somewhat broader anteriorly than posteriorly; the 

 epimeron of the third segment and that of the fourth also are the same 

 width throughout their length; those 

 of the last three segments are increas- 

 ingly wider posteriorly. 



All the legs are similar in structure; 

 the propodus is furnished with numer- 

 ous stiff bristles along the proximal 

 half of the inferior margin. 



The abdomen is composed of two 

 short segments and a long terminal one 

 having lateral rudiments of another 

 partially coalesced segment. The ter- 

 minal segment has the sides somewhat 

 concave, the post - lateral angles 

 rounded, and an acute median terminal 

 point triangularly produced with apex 

 rounded. The opercular valves are in 

 two parts each; a long anterior portion, crossed obliquely by a faint 

 carina, and a short posterior portion. 



Only one specimen of this species, a male, was collected at Monterey 

 Bay by Mr. Harold Heath. It agrees in every detail with Stimpson's 

 and Mier's descriptions. No figure has ever been given. 



FIG. 406. PENTIDOTEA WHITEI. a, MAXIL- 

 LIPED. x 15}. b, FIRST ANTENNA, x 15y. 



