124 CALIFORNIA ACADEMY OF SCIENCES. 



ambulatory legs are subequal, crested above for a part of their length; 

 dactyls with curved, acute tips. Abdomen flattened, triangular, fitting 

 neatly into a depression in the sternum; behind the entire basal segment 

 the abdomen beuds abruptly, and the three following segments are divided 

 into a median row of plates with a series of lateral plates on either side; 

 the penultimate segment is devoid of lateral plates and conceals the 

 minute, triangular telson. 



Type. — C. ty incus Brandt. 



Cryptolithodes typicus Brandt. 



CryptoUthodes typicus Brandt, Bull, phys-math. Acad. St. Petersb., Tome 

 VII, 1849, p. 175; and Tome XI, 1853. Stimpson, Journ. Bost. Soc. 

 Nat. Hist., Vol. VI, 1857, p. 472, PI. XIX-; Proc. Acad. Nat. Sci. 

 Phila., 1858, p. 231. Bate, Proc. Zool. Soc. Loudon, 1864; in Lord's 

 Nat. in Vancouver's Is., Vol. II, 1866, p. 271. Bocvier, Ann. Sci. 

 Nat. (7), Tome XVIII, 1895, p. 189, and (8), Tome I, 1896, p. 28. 



Carapace very wide. Kostrum very much deflexed, not distally widened, 

 'the upper surface rounded, the anterior extremity truncated with the 

 angles rounded. Lateral angles of the carapace acute; the posterior mar- 

 gin bulges outward very slightly in the middle. Seen from below the 

 carapace is strongly concave and not at all flattened out towards the sides. 

 The depression between the cardiac and median region is shallow. Teeth 

 on the posterior margin of the carapace obscure; those on the antero" 

 lateral margin small. Orbital sinus much less deep than in sitchensis. 

 Chelipeds very low, rounded tubercles; large hand with the outer surface 

 tuberculated and the upper side rounded; small hand acute above. The 

 merus joints of the ambulatory legs are furnished below with a deep 

 groove bounded by the sharp, produced, lower margins. Abdomen crossed 

 by transverse ridges. 



Described from a small, dried specimen in the U. S. 

 National Museum (No. 3475) collected by Dall at Bel- 

 koffsky Bay, Alaska (25 fathoms). 



Northern California (Brandt); Monterey (Stimpson); 

 Vancouver's Is. (Bate). l.^At- ... 



