94 HISTORY OF BRITISH CRUSTACEA. 



Mr. Say* describes a species of this genus as indigenous 

 to the United States ; the exuviae of this, particularly of its 

 large front foot, occur very frequently on the sea-beach of 

 the southern States, early in the spring. The Crab itself is 

 seldom seen, owing to its recluse mode of life. He found 

 the living specimen by digging iu the sand of the bay shore 

 of the river St. John, in East Florida, about eighteen inches 

 below the surface. "It had formed a tubular domicile, 

 which penetrated the sand in a perpendicular direction to a 

 considerable depth, the sides were of a more compact con- 

 sistence than the surrounding sand, projecting above the 

 surface about half an inch or more, resembling a small 

 .chimney, and rather suddenly contracted at top into a small 

 orifice. The deserted tubes of the Callianassa are in many 

 places very numerous, particularly where the sand is indu- 

 rated by iron into the incipient state of sandstone ; they are 

 always filled up, but may be readily distinguished by the 

 indurated walls and summit often projecting a little above 

 the general surf ace. " 



Callianassa subterranea, Mont. sp. Mud-burrower. 

 (Plate VII. fig. 2.) — Colour during life more or less orange, 

 sometimes yellow on the sides and on the tail, the arms 



* Journal of the Academy of Natural Sciences of Philadelphia, i. p. 240. 



