THE SPIDER CRABS OF AMERICA 195 



Species of Pisinae wrongly ascribed to America: 



Cancer hircus Fabricius, Species Insectorum, vol. 1, 1781, p. 503; Jamaica. 

 =Pisa tetraodon (Pennant, 1777), a European species. Type examined 

 (Kiel Mus.). 



Genus SCYRA Dana 



Scijra Dana, Amer. Journ. Sci.,ser. 2, vol. 11, 1851, p. 269; type, S. acutifrons 

 Dana; U. S. Expl. Exped., vol. 13, Crust., pt. 1, 1852, p. 94. — Holmes, 

 Occas. Papers California Acad. Sci., vol. 7, 1900, p. 41. 



Carapace subpyriform, tuberculated, having a few or no spines. 

 Rostrum composed chiefly of two flattened horns. Orbits small, with 

 a fissure above and below, the lower and sometimes the upper one 

 being open. Preorbital spine present. Basal antennal article rather 

 narrow, with a small spine at antero-external angle, the two following 

 articles compressed and not concealed by rostrum. Merus of maxilli- 

 peds distally truncate, notched at antero-internal angle. Chelipeds 

 of male well developed, hand compressed and carinated above, fingers 

 acute. Legs moderately long and narrow, diminishing rather regu- 

 larl}^ in length from first to fourth. Abdomen 7-segmented in both 

 sexes. (After Holmes.) 



Inhabits the west coast of North America and the coast of Japan. 



SCYRA ACUTIFRONS Dana 



. SHARP-NOSED CRAB 



Plate 79; plate 224, figs. 4 and 5 



Scyra acutifrons Dana, Amer. Journ. Sci., ser. 2, vol. 11, 1851, p. 269 (type- 

 locality, in man Oregonensi; type not extant); U. S. Expl. Exped., vol. 

 13, Crust., pt. 1, 1852, p. 95, pi. 2, figs. 2a-2ci. — Holmes, Occas. Papers 

 California Acad. Sci., vol. 7, 1900, p. 41. 



Diagnosis. — Carapace of adult without a spine on hepatic or 

 branchial margin. Margins of arm tuberculate, not cristate; dactylus 

 of chela with a large, subbasal tooth. Ambulatory legs subcylindrical, 

 dactyli rather stout. 



Description. — Carapace covered with tubercles; gastric region 

 tumid, separated from cardiac and branchial regions by a conspicuous 

 depression; an acute or spiniform tubercle near the center of the 

 gastric region, behind which there is a larger, obtuse tubercle.. Bran- 

 chial regions tumid, bearing at the widest part a large, projecting 

 tubercle, in front of which lies an elevation which may bear several 

 small tubercles though often smooth. A very large tubercle on the 

 cardiac and a small one on the intestinal region. Rostrum short, 

 horns ovate-lanceolate, occupying over half the length. Preorbital 

 spine small, acute. A lobe on outer margin of basal antennal article 

 and immediately behind it, a tooth in line with the very prominent 



