Boone, Crustacea, Cruises of "Ara" and "Alva" 275 



Mr. Stimpson's figure of P. rupicola (1857, pi. 19, fig. 2), 

 shows the carpus of the cheliped 14.5 millimeters long, 8.5 milli- 

 meters wide, the carapace 17 millimeters long and 17 millimeters 

 wide. Of his P. eriomerus, he states, "Chelipeds (except at the 

 fingers) granulated, carpus rather elongated, with a straight and 

 entire anterior margin destitute of a prominent inner lobe, and 

 a denticulated posterior margin ; hand with a tuft of hair between 

 the fingers below. Ambulatory feet everywhere hairy on upper 

 edge. Surface of meros of third pair also hairy." 



Examination of all available material and records, including 

 the present Chilean series of specimens, shows in the specimens 

 examined a range in the length of the carpus of chelipeds from 

 width equal to length, 5 millimeters long and 5 millimeters wide 

 on the right, regenerated chela, with a 10 millimeters wide and 

 15 millimeters long, or 1.5 times as long as wide, carpus on the 

 opposed left chela of the same male, to specimens having a one 

 and one-third to one and one-half, or one and three-fourths to 

 twice as long as wide, carpal joint of the chelipeds. 



In Mr. Holmes' illustration of the cheliped of eriomerus^ 

 actual measurement of the drawing shows the carpus to be two 

 and one-half times as long as wide, but no certainty exists, nor 

 does the drawing itself indicate, that it was done to scale. 



In the thirty-odd specimens examined by the present writer 

 a wide individual variation exists also in the degree of granu- 

 lation of the carapace and legs, varying from smooth or finely 

 punctuate, in the soft-shell specimens and "peelers" to partially 

 granulose and very granulose, the large old males and females 

 usually showing the greatest amount of granulation and branchial 

 striation, but in instances of regenerated chelae possessing simul- 

 taneously with such granulose bodies, smooth or nearly smooth 

 chelipeds. 



The prominence of the inner lobe of the carpus is also too 

 variable to be counted a species character, being actually larger 

 in the old specimens, appearing larger in those with shortened 

 carpal joints and being reduced in soft shell forms or even absent 

 in the regenerated legs. 



All specimens examined have the ambulatories setigerous on 

 the distal three articles and in greater or less degree also on the 

 merus of the third pair of legs, this setigerous condition being 

 conspicuous on young specimens and also on a few of those from 



