1921] Schmitt: The Marine Decapod Crustacea of California 279 
KEY TO THE CALIFORNIA SPECIES oF UCA 
I. Carapace very convex, semi-cylindrical. Male with an oblique stridulating 
ridge near proximal lower corner of inner surface of large hand; abdomen 
of male with third to sixth segments fused. 
musica, p. 280. 
II. Carapace moderately convex, not semi-cylindrical. Male without stridulating 
apparatus; abdomen of male, inclusive of telson, seven-jointed. (Not 
known north of False Bay.) 
crenulata, p. 279. 
Uca crenulata (Lockington) 
Plate 49 
Gelasimus crenulatus Lockington, Proce. Calif. Acad. Sci., 7, 149, 1876 
(1877). 
Gelasimus gracilis Rathbun, Proc. U. S. Nat. Mus., 16, 244, 1893. 
Uca crenulata Holmes, Oceas. Papers Calif. Acad. Sci., 7, 75, pl. 1, figs. 
7-9, 1900; Rathbun, H. A. E., 10, 190, 1904; Rathbun, Bull. U. S. 
Nat. Mus., 97, 409, pl. 146, 1918. 
a b 
Fig. 164. Uca crenulata; a, carapace; b, inner side of large hand (after 
Holmes). 
Characters.—Carapace smooth, moderately convex; lateral margins nearly 
parallel for a short distance behind the prominent, somewhat forwardly directed, 
acute anterolateral angles, then converging; front nearly one-third the width 
of the carapace. Hand of large cheliped of male finely granulated on outer 
surface, inner surface with an oblique granulated or tubereulated ridge which 
makes an obtuse angled turn in running from the lower to the upper margin. 
Ambulatory legs pubescent; merus transversely rugose. Abdomen of male, 
inclusive of telson, seven-jointed. j 
Dimensions.—Length 10 mm., width 15 mm. (Rathbun). 
Type Locality —Todos Santos Bay, near San Diego, California. 
Distribution—From False Bay, San Diego County, California, to Gulf of 
California (Rathbun). 
