40 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxn. 



peduncle, furnished at the tip with a spine and a few hairs, and a few 

 short hairs on the inner margin. 



Telson cleft to the base, the lobes rounded distall}^ and furnished 

 with a few hairs and a few small spines. 



Length, 10 mm. 



Type locality. — Point Arena, California. Specimens from Portland, 

 Oregon, were also examined. These were larger and stouter than 

 those from California. 



Type.—C^i. No. 32841, U.S.N.M. 



GAMMARUS FASCIATUS Say. 



Gammarus fasciatus Say, Jour. Acad. Nat. Sci. Phila., I, 1817, p. 374. — De Kay, 

 Zool. of New York, VI, 1844, p. 37. — Bate, Cat. Amphipodous Crustacea 

 British Mus., 1862, p. 210, pi. xxxvii, fig. 6.— Smith, Rep. U. S. Fish Com., 

 1872-73 (1874), p. 653.— Forbes, Bull. 111. State Lab. Nat. Hist., No. 1, 

 1876, p. 6. 



E3-es reniform; their distance apart slightl}^ exceeding their diame- 

 ter. First antennae with the first and second segments nearly equal 

 in length and twice as long as the third; fiagellum twice as long as the 

 peduncle and composed of about thirt}^ segments; secondary iiagellum 

 as long as the second segment of the peduncle and consisting of five or 

 six segments. Second antennae about two-thirds the length of the 

 first; peduncle exceeding that of the first pair, with the two distal 

 segments elongated and nearly equal; fiagellum slightly shorter than 

 the peduncle and composed of about fifteen segments. 



In the male the carpus of the first gnathopods is triangular, slightly 

 longer than broad; propodus not quite twice as long as broad, much 

 narrowed distally; palm slightl}" concave, very oblique, continuous 

 with the posterior margin, with a narrow lamellar edge, armed with 

 a few long hairs, near the middle of the inner side with a stout spine, 

 at the base of which there is a fascicle of long hairs, and three or 

 four smaller spines near the tips of the closed dactyl; posterior margin 

 with four or five fascicles of long hairs; dactyl strongly curved and 

 half as long as the propodus. Propodus of the female much smaller 

 than that of the male, only slightly narrowed distall}^; palm not so 

 oblique as in the male, furnished with a few long hairs and a few 

 spines at the tip of the closed dactyl, but without a spine at the middle 

 of the palm. 



Propodus of the second gnathopods in the male as long as in the 

 first pair, broadest distally; lateral margins nearly parallel; the poste- 

 rior margin furnished with numerous fascicles of hairs; palm oblique, 

 but not so much so as in the first pair, concave in the middle, armed 

 with a few short hairs at the base of the broad lamellar edge, a stout 

 median spine, and three or four smaller ones at the tip of the closed 

 dactyl; dactyl not so strongly armed as in the first pair, as long as 



