ACADEMY OF SCIENCES. 151 



centre of its length, and several smaller teeth. Distal end of manus forming 

 an angle of about 80° with the superior margin, and of about 60° with the 

 propodal finger, which does not increase greatly in width towards its base. 

 Dactylus slender with a large tooth nearer the base than the tip, which is in- 

 flated and spoon-shaped. Inner surface of the hand, towards the margins, 

 armed with scattered tubercles of small size. Upper portion of manus curv- 

 ing inwards posteriorly, the carpus fitting, when the hand is bent, into the 

 hollow between the upper incurved carina and lower thick portion of the 

 manus. The smaller hand is similar to the larger. The stoutness of body of 

 this crustacean is such that the sides of the branchial and hepatic regions are 

 visible from above, and protrude laterally beyond the antero-lateral carina. 

 The male appendages agree with those of C. crassum. 



M. M. 



Greatest length of carapax, measured along its convexity .... 100 



Greatest width of carapax 101 



Length of larger hand to end of propodal finger 127 



Length of larger hand from carpus to base of dactylus 40 



Greatest width of larger hand 58 



Width of carapax between antero-lateral carinae in front y3 



If this should prove, on examination of more specimens, to be a new 

 species, I propose to name it Cardiosoma latimanus. 



Gqearcinns quadratus. De Saussure. Eevue et Mag. de Zool., v., 360; pi. 

 xii., f. 2. 



The work above referred to is not accessible to me In Mr. S. I. Smith's 

 Notes on American Crustacea, Trans. Coun. Acad., vol. ii., Cardiosoma quad- 

 raium, Saussure, is referred to. Are they identical ? 



The male appendages of C. quadratum figured in the plate iv. of the notes 

 cited above differ from those of the Cardiosoma described under C. crassum. 



Mazatlan. 



BOSCIAD^. ' 



Potamocarcinus armatus. M. Edwards. Archiv. du Mus., vii., 174; pi. xiii. 

 Obtained in the North Pacific Exploring Expedition in Lake Nic- 

 aragua. Stimpson. Prod, des Animal, evert, p. 46. 



GKAPSID^. 



15. Grapsus strigcsus. Latreille. Stimpson, Crust. & Echi., P. S. N. A., 

 says: " Specimens in the Brit. Mus. from Lower California are referred to 

 this species by White." White, Brit. Mus. Cat. Crust., p. 40. 



Numerous specimens of a Grapsus from Lower California agree in every 

 respect with the remarks upon this species in Dana's Crust. U. S. Ex. Exp., 

 vol. 1, p. 338 ; having the merus of the right posterior legs three-toothed at 

 its distal end, instead of entire, as in G. pictus. 



No. 52. Mazatlan, dried. Henry Edwards. 



No. 53. Locality unknown, dried. Donor unknown. 



Proc. Cal. Acad. Sci., Vol. VII.— 11. 



