NO. 1175. 



ISOPODS OF THE PACIFIC COAST— RICHARDSON. 



833 



and extend in an anterior direction, the other five pairs extend in a pos- 

 terior direction. 



The type and only specimen was collected by Mr. Heath at Monterey 

 Bay, California, at the surface. Fo. 22508, U.S.N.M. 



22. DYNAMENE TUBERCULOSA, new species. 



Body oblong-ovate; color, light yellow, almost white; surface of abdo- 

 men tuberculated. 



Head large, much broader than long, with a wide anterior margin, 

 broadly curving on either side of a small median 

 point. Eyes small, and situated at the extreme 

 post-lateral angle of the head. The first pair of 

 antenna', composed of eight articles, reach beyond 

 the middle of the first thoracic segment. The sec- 

 ond pair of antenn.T, compo.sed of twelve articles, 

 extend to the posterior angle of the first thoracic 

 segment. 



The first segment of the thorax is one and a 

 half times longer than any of the other segments, 

 which are about equal in length. The epimera, 

 which are distinctly marked, and roundly produced 

 at their i)osterior angles, are much broader than 

 long. 



The first abdominal segment is transversely 

 crossed by three suture lines, indicated at the sides 

 of the segment. Three small tubercles are situated 

 in a transverse line on the posterior margin of this 

 segment. The terminal segment is subtriangular 

 in shape with a broad funnel-like excavation at its 

 extremity, formed by the infolding of the lateral 

 edges. The anterior part of the termiiuil segment 

 is very convex, upon which elevation are situated 

 three large tubercles in a transverse row, the cen- 

 ter one being in the median line. At the base of 

 the terminal excavation is also a small tubercle. 

 Both branches of the uropoda are similarly shaped, 

 being of the same width throughout their entire 

 length and rounded posteriorly. The outer branch 

 is somewhat shorter than the inner brantjh; neither reach the extrem- 

 ity of the abdomen. 



Individuals were found at (Jrualala, California, on llaliotis rufesceiiSj 

 by Dr. K. E. C. Stearns; also, one specimen at Catalina Harbor, Cali- 

 fornia, and one at Popofit" Island, Aleutian Islands, at low water, by 

 Mr. W H. Dall. 



Type.—'^o. 22569, U.S.KM. Popoff Island, Aleutian Islands. 

 Proc. ]Sr. M. vol. xxi y.i 



Fio. 9.— Dynamene tu- 



IlEKCULOSA. X 8. a, 

 nOKSAI. VIEW; b, LAT- 

 ERAL VIEW. 



