CRUSTACEA NORTH PACIFIC EXPLORIXG p:xpEDITIOX 35 



41. CANCER ANTENNARIUS Stimpson 



Cancer antt'iiiiarins Stimpson, Proc. Cal. Acad. Nat. Sci., i, 88; Jour. Bost. 

 Soc. Nat. Hist., vi, p. 462 [22], pi. xviii, 1857. 



Carapax convex; proportion of length to breadth in male, i : 1.52; 

 in female, i : 1.45; greatest breadth at the penultimate antero-lateral 

 tooth. Surface much undulated, very smooth in appearance, but 

 minutely granulated, the granulation being almost obsolete about 

 the middle, but sufficiently well marked toward and at the margin, 

 x^ntero-lateral margin convex and well rounded, with nine teeth, 

 the first one forming the angle of the orbit; teeth deeply separated, 

 their edges denticulated, their apices curving forward and very 

 sharp, almost uncinate. Postero-lateral margin with a deep emar- 

 gination near the extremity, forming a sharp tooth, and another, 

 rather slight, a short distance within the first. These emarginations 

 are much deeper in the young than in the adult. Front sufficiently 

 broad, but not projecting beyond the exterior angle of the orbit; 

 interantennary portion with three well-separated teeth, .the middle 

 one being smaller and rather below the lateral ones ; prseorbital tooth 

 rather prominent. External antennae very large and hairy, in length 

 equaling two-fifths that of the carapax; apex of basal joint project- 

 ing considerably beyond the prseorbital tooth. Meros of hectognath- 

 opoda subquadrate, a little longer than broad ; anterior margin nearly 

 transverse, ciliated with long hairs ; angles rounded ; notch for inser- 

 tion of carpal joint deep, abrupt below, continuous with the margin 

 above. The slight ridge on the palate near to and parallel with its 

 inner margin is more sharply prominent in this than in other species. 

 Chelopoda large, particularly in the male ; carpus and hand rather 

 short and thick, in the adult smoothly rounded above and microscop- 

 ically granulated ; in the young ornamented with small spiniform 

 tubercles ; costse on the hand well marked and granulated in the 

 young, but almost obsolete in the adult. Fingers in the female sul- 

 cated. Ambulatory feet hairy ; meros overreaching the margin of 

 the carapax ; dactylus with thick brushes of short hair along the 

 angles. Margins of abdomen and other parts on the inferior surface 

 generally, very hairy. Terminal joint of abdomen in the male slen- 

 der, with somewhat concave sides and bluntly pointed extremity. 



Color above dark purplish-brown; below yellowish-white, spotted 

 with red ; fingers black. Dimensions of carapax in a male : Length, 

 2.43; breadth, 3.70; in a female, length, 2.13; breadth, 3.08 inches. 



This species is not uncommon on the coast of California, inhabit- 

 ing rocky bottoms in the laminarian zone. 



