176 University of California Publications in Zoology [Vou 23 
Pachycheles rudis Stimpson 
Plate 33, figure 2 
Pachycheles rudis Stimpson, Ann. Lye. Nat. Hist. N. Y., 7, 76, pl. 1, fig. 5, 
1859 (1860); Lockington, Ann. Mag. Nat. Hist. (5), 2, 394, 1878; 
Holmes, Oceas. Papers Calif. Acad. Sci., 7, 109, 1900; Rathbun, H. A. 
E., 10, 168, pl. 6, fig. 6, 1904; Baker, Rep. Laguna Mar. Lab., 1, 102, 
1912. 
a b 
Fig. 111. Pachycheles rudis, 2; a, dorsal view, natural size (from Stimpson) ; 
b, telson, X 2. 
Characters.—Chelipeds unequal, with a rugose, irregularly tuberculated and 
granulated upper surface, provided with a few scattered coarse hairs, of which 
only a few, if any, are to be found in the gape of the fingers of the larger hand. 
In the sulci between the granules there is a faint pubescence, which is scarcely 
evident to the naked eye and which never in the least obscures any of the granu- 
lations. 
The large, prominent, granulated tubercle on the median distal portion of the 
palm is low and rounded, about as high as wide at the base, or less; occasionally 
several longitudinal lines of larger granules are evident behind the large tubercle 
but they are always more or less inconspicuous and never attain the prominence 
of those similarly placed in P. holosericus. 
The immovable finger of the larger hand exceeds half the length of the movable 
one; on the cutting edge of the movable finger, near its base, there is a large, white 
bilobed or double tooth, while near the upper end of the cutting edge of the 
immovable finger there is a large tuberculiform tooth. The laminate anterior 
margin of the carpus is granulate along the edge, giving it a minutely denticulate 
appearance; rarely if ever is there any suggestion of larger teeth, other than the 
one comprising the entire laminate portion. 
The telson is composed of five plates; a central (triangular), two terminal, 
and two lateral. 
Dimensions.—Type, male: length of carapace 10.9 mm., width 11.7 mm. 
Type Locality Monterey, California. 
Distribution.—Kadiak, Alaska, to San Diego, California; Lower California 
(Lockington ). 
