ISOPODS OF NORTH AMERICA. 221 



The segments of the abdomen are all distinct. The sixth or terminal 

 segment is a little broader than long, 6 mm. : 5 mm., almost quadrate, 

 with the post-lateral angles rounded and a small triangular point in 

 the middle of the posterior margin. The uropoda are longer than the 

 terminal abdominal segment. Both branches are produced to long, 

 narrow, acute extremities, the outer branch being slightly narrower at 



FIG. 223. NEROCILA ACUMINATA. a, MAXILLIPED. x 27j. 6, FIRST MAXILLA, x 27|. c, SECOND MAX- 

 ILLA, x 27J. d, PALP OF MANDIBLE, x 27}. e, SEVENTH LEG. x 9|. 



the base and somewhat longer than the inner branch. The inner 

 branch is 3 mm. long; the outer branch 4 mm. in length. 



The legs are all prehensile, slightly increasing in length, with long, 

 curved dactyli. 



There are two longitudinal bands or stripes of a light-brown or j^el- 

 low color extending the entire length of the body, one on either side 

 of the median line. The other parts of the body are dark greenish 

 brown. 



NEROCILA CALIFORNICA Schioedte and Meinert. 



Nerocila californica SCHICEDTE and MEINERT, Naturhistorisk Tidsskrift (3), XIII, 

 1881-83, pp. 72-76, pi. v, figs. 12-13; pi. vi, figs. 1-2. RICHARDSON, Proc. 

 U. S. Nat. Mus., XXI, 1899, p. 830; Ann. Mag. Nat. Hist. (7), IV, 1899, p. 

 172; American Naturalist, XXXIV, 1900, p. 220. 



Localities. San Diego, California; Taboga Island, Panama Bay; off 

 Point Sur, California; National City, California. 



Parasites of Promicrops guttatm; cat-fish on fin; Gyropleurodus 

 francisci on dorsal fin : on dorsal and caudal fin of Paralabrax clathrata, 

 Scorpa&na guttata, Triakis semifasciata, Myliobatis sp. 



Body oblong-ovate, nearly two and a half times longer than wide, 

 8 mm. : 19 mm. 



Head, wider than long, 2 mm. : 3 mm., with the anterior margin 

 widel} T rounded, the posterior margin produced in three lobes, the 

 middle one of which is much the larger. The eyes are indistinct and 

 have almost entirely disappeared. They have degenerated, probably 

 owing to the parasitic mode of life, and are certainly f unctionless. The 

 first pair of antennae are composed of eight articles and extend to the 

 end of the seventh article of the second pair of antennae. The second 



