54 CALIFORNIA ACADEMY OF SCIENCES. 



The specimen described by Mr. Walker was referred 

 by him to Bate's species only with great hesitation, as 

 Bate's 'imperfect description would apply quite as well 

 to T. oregonensis.'' The determination is made solely 

 on the ground that Bate calls recurvidens a ''pretty spe- 

 cies" — a term which applies better to Walker's specimen 

 than to the less attractive species of Dana. I do not 

 believe, however, that Walker's identification is correct, 

 as Bate says that recurvidens ''may be distinguished by 

 the sharp points of the inner lateral teeth, granulated 

 or minutely baccated along the margin and having the 

 apex recurved." The teeth of the specimen described 

 by Walker, instead of being sharp pointed, are distally 

 widened with a wide, transverse, distal margin. The 

 form that Mr. Walker describes has, therefore, been 

 given a new specific name. Bate's species may be T. 

 oregonensis or, as Miers has suggested, the young of 

 Cancer antennarius Stimpson. 



Trichocarcinus oregonensis Dana. 



Trichocera oregonensis Dana, Proc. Acad. Nat. Sci. Phila., Vol. VI, 1852, 



p. 86; Crust. U. S. Expl. Expd., Part I, 1852, p. 299, PI. XVIII, fig. 5. 



Stimpson, Journ. Bost. Soc. Nat. Hist., Vol. VI, 1857, p. 464. Whit- 



'eaves. Can. Nat. (2), Vol. VIII, 1878, p. 471. 

 Trichocarcinus oregonensis Miers, Proc. Zool. Soc. London, 1879, p. 34; 



Challenger Keports, Vol. XVII, 1886, p. 110. Smith, Eep. Prog. Geol. 



Sur. Canada, 1878-9, B, p. 207. Newcombe, Bull. Nat. Hist. Soc. 



Brit. Col., 1893, p. 24. Walker, Trans. Liverpool Biol. Soc, Vol. 



XII, 1898, p. 271, PL XV, tig. 2. 



Carapace elliptical, evenly rounded at the sides; areas distinct and ele- 

 vated, especially in front, and covered with rounded granulations; sulci 

 between the elevations wide, deep and smooth, especially on the anterior 

 portion of the carapace. The front does not project beyond the line of the 

 orbits; the outer pair of teeth (preorbital) are lobe-like, having a broad, 

 granulated edge, and are separated from the inter-anteunary portion of the 

 front by a deep, concave notch; the median portion of the front is very 

 short, truncated, and obscurely divided by a slight incision on either side 



