80 CALIFORNIA ACADEMY OF SCIENCES. 



arcuated; a single tooth at the outer angle of the front; behind the front 

 are four lobe-like prominences, the two middle ones the more conspicuous, 

 and separated from each other by a groove whose sides are marked with 

 sharp lines. A single tooth on the lateral margin behind the prominent 

 postorbital. The notch at the infero-external angle of the orbit is deep. 

 Orbits deep, the inferior margins strongly granulated. Antennae minute. 

 Merus of the maxillipeds quite strongly produced at the antero-internal 

 angle; first joint of the palp large and compressed. Merus of the cheli- 

 peds short, trigonal, and transversely rugulose, the anterior margin 

 laminate and armed at the distal end with three teeth; carpus finely rugose 

 externally and bearing a tooth or tubercle at the antero-internal angle; 

 hand in the adult male larger than all the preceding joints combined; a 

 raised line usually present on the upper side of the palm and a delicate 

 line on the lower portion of the outer surface. Merus joints of the legs 

 transversely rugulose, strongly compressed and expanded, especially in 

 the last three pairs, the postero-distal angles in the anterior pairs armed 

 with a variable number of teeth; in the last or last two pairs they are 

 rounded and usually edentate; dactyls short, compressed, and spinous on 

 both margins. Third joint of the abdomen in the male strongly convex at 

 the sides; following joints increasing successively in length. 



Length of carapace, male 36.5 mm. 



Breadth of carapace, male 41 mm. 



Length of carapace, female 30 mm. 



Breadth of carapace, female 34 mm. 



Japan (Stimpson, Ortmann), Sandwich Islands (Ran- 

 dall), Oregon! northern California! San Francisco Bay! 

 Monterey! San Diego! Gulf of California (De Man). A 

 very common species on rocky shores. 



This species was originally reported by Randall from 

 the Sandwich Islands, where it has not since been found. 

 On the other hand, P. parallelus, which Randall reported 

 as coming from the Columbia River, has not since been 

 found on the west coast of the United States. It is 

 probable, as Stimpson suggests, that the labels of the 

 two species were accidentally exchanged. Several other 

 species reported from this coast by Randall have not 

 since come to light. Possibly mixing of labels has 

 occurred in other cases also. 



