ISOPODS OF NORTH AMERICA. 



91 



Two specimens, from Monterey Bay, California, collected by Mr. 

 Heath from sandy shore at mean tide. 

 7^. Cat. No. 22564, U.S.N.M. 



CIROLANA CHILTONI, new species. 



Body oblong-ovate, a little more than twice as long as wide, 5 mm. : 

 11 mm. 



Head wider than long, about twice as wide as long, 1 mm. : 3 mm. 

 with the front produced in a prominent process which widens anteri- 

 orly beyond the antennae, arches over them and is confluent with the 

 frontal lamina. The eyes are large, composite, and occupy the antero- 

 lateral corners of the head. The first pair of antenna? have the first 

 article large, the second article somewhat shorter, and the third article 

 about one and a half times longer than the second. 

 The peduncle extends to the posterior margin of 

 the head. The flagellum, which is composed of fif- 

 teen articles, extends to the posterior margin of 

 the third thoracic segment. The second pair of 

 antennae have the first two articles extremely short 

 and about equal in length; the third and fourth 

 are subequal and each article is about as long as the 

 first two taken together; the fifth article is twice 

 as long as either of the two preceding articles. 

 The peduncle of the second antennae extends to the 

 middle of the first thoracic segment. The flagel- 

 lum is composed of thirteen articles and extends a 

 little beyond the post-lateral angle of the fifth 

 thoracic segment. 



The seven thoracic segments are subequal in 

 length. Epimera are distinct on the last six seg- 

 ments. The last three have the post-lateral angles slightly produced 

 beyond the posterior margins of the segments. 



The first segment of the abdomen is short, being partly covered by 

 the seventh thoracic segment. The second, third, and fourth seg- 

 ments are equal in length and width. The fifth segment is as wide as 

 the preceding segment, and the lateral parts are not covered by the 

 lateral angles of the fourth segment. This segment is a little longer 

 than any of the three preceding segments in the middle of the dorsal 

 surface. The sixth or terminal segment is posteriorly triangular, with 

 apex acute. The inner branch of the uropoda is very broad and 

 obliquely truncate, the outer and inner posterior angles being acute. 

 The outer branch is narrow and posteriorly rounded; it extends to 

 the outer posterior angle of the inner branch. Both branches, as well 

 as the posterior margin of the terminal segment are fringed with long 

 hairs. The base of the terminal abdominal segment is raised above 



FIG. 73. CIROLANA 

 CHILTONI. a, HEAD, x 

 9. b, POSTERIOR PART 



OF ABDOMEN. X 9j. 



