ACADEMY OF SCIENCES. 67 



three times as long as rostrum. Upper surface of carapax hirsute, especially 

 upon the rostrum. Hinder part of sternum and abdomen tomentose. Chel- 

 ipeds almost as long as second pair, without hairs; merus with about four teeth 

 on its superior margin; carpus slightly tubercular; manus perfectly smooth. 

 The movable finger occasionally has a tubercle between the base and the tip. 

 Movable and fixed fingers serrated for half their length and interlocking on ' 

 their outer margins. Hinder feet hirsute, short, a spine ou the upper sur- 

 face of the fourth joint of second and third pairs. 



Color, reddish-brown above, the hands and under parts white, marbled with 

 bright red, the latter predominating on the upper surface of the chelipeds. 



Localities: La Paz, Mulege Bay, Port Escondido, San Jose Island, all in 

 the Gulf of California. 



It is found under stones at low tide, and was also brought up at La Paz by 

 the dredge. 



The females have no tubercle on the inside of the dactyli, and the spines 

 upon the branchial region are not prominent. They were with ova when col- 

 lected, in the month of August. 



M.M. M. M. 



Length of carapax 20 13 



Width of carapax 17 12 



The females are rather less elongated than th9 males. The carapax in both 

 sexes is exceedingly overgrown with corallines, sponges, sertularia, etc. 



No. 16. Two males and two females, in spirits. Fisher and Lockington. 



This little crab evidently belongs to the Pisince, but does not fit well into 

 any of the genera given by Dana. The characters are nearest those of 

 Pisoides and Herbstia, but from the former it differs in the presence of a pre- 

 orbital spine, and from the latter in the great width of the fixed joint of the 

 external antenna?, as well as in the small size of the chelipeds. 



I think it not unlikely that this form is the Herbstia parvifrons of Dr. Kandall, 

 (Proc. Phil. Acad. Sci., 1869, p. 107), but his description is so short that it 

 is impossible to be certain; so far as it goes, however, tye characters given 

 agree. 



13. Pisoides? iumidus. Lockington, Proc. Cal. A.cad. Sci., Feb. 6, 1876. 



I have received specimens of this species from San Bartolome Bay and 

 Magdalena Bay, all of them smaller than the type in the possession of the 

 Academy. Those from Magdalena Bay were dredged in three fathoms. 



The first article of the external antennae is acute on its outer angle, but can 

 scarcely be called a spine, the second and third are long, ciliated, and cylin- 

 drical, in the last character differing from the generic description given by 

 Dana. 



No. 6. Female. San Diego, between tides. Hy. Hemphill. 



LIBINItOE. 



Libinia canaliculata? Say. 



14. Libinia affinis? Kandall. Jour. Acad. Nat. Sci., Phil, VIII, 107. 



Gibbes, Proc. Am. Asso., 1850, p. 170. Stimpson, Crust, and Echi. 

 Pac. S. N. A., 14. Hale Streets, Proc. Acad. Nat. Sci., Phil., 1870 

 p. 170. 



