32 Crustacea and Echinodermata of the 



stomachal region anteriorly, and on the intestinal poste- 

 riorly. There may be either several small granules or one 

 large one only, on the margin between the posterior teeth. 



Upper California, (Nuttall.) 



Mus. Phil. Acad. ; Smithsonian. 



DECAPODA ANOMOURA. 



Tribe LITHODEA. 



cryptolithodes typicus. Brandt. 



Plate XX. 



Cryptolithodes typicns, Brandt; Bulletin physico-matJiim.de I' Academie de St. 

 Petersb. 1849, vii. 175. 



As Brandt's description of this remarkable crab is unac- 

 companied by a figure, and very short, — the general charac- 

 ters of the clypeus, rostrum, and ante n nary appendix only 

 being given, — I take the present opportunity of presenting fig- 

 ures, and a detailed description, drawn up from a specimen (a 

 female) seal in a dried state to the Smithsonian Institution 

 by Mr. Taylor of Monterey. As the dismemberment of 

 this most rare and unique example would be by no means 

 desirable, the details of the inner maxillipeds, and of some 

 oilier less conspicuous appendages, cannot be here given. 



The most striking characteristic in this species is the 

 great development of the carapax, which forms a broad, 

 thin shield, of very uneven surface, completely hiding the 

 legs, antennae, abdomen, and all the inferior parts of the 

 body. These parts, therefore, which form a great portion 

 oi' the bulk in most crabs, seem here, when viewed from 

 below, to be placed in the bottom of a cup-like cavity. This 

 arrangement would lead one to refer the species to the 

 Cryptopodiacece, to which family however it has no resem- 

 blance in its other characters; the structure of the antenna?, 

 the position of the eyes, and the concealment of the posterior 

 pair of feet at once distinguishing it. 



