\r.\v sit.( n> of the (;f,\i s kSTACl 8. H. » 



inwards, the innermost the longest, terminating in a small 

 spine opposed to the thumb: caudal lamellae ciliated, lateral 

 segments with an elevated longitudinal spine ; the penulti- 

 mate and antipenultimate legs of the male furnished with an 

 obtuse apophysis at the base of the second joint. 



Dimensions. — Length from the tip of the rostrum to the 

 tip of the tail, three inches eight-tenths; breadth of the tho- 

 rax one inch: length of the anterior feet nearly four inches; 

 length of the hand and finger nearly equal. 



The presenl species 3 in size and markings, is most nearly 

 allied to the A. affirm of Say: but differs in the form of the 

 rostrum, in the proportional length of the arms: in being fur- 

 nished in the male with an apophysis on the third joint of 

 i tli the penultimate and antepenultimate legs; in the dispo- 

 sition of the -pines: and in being tuberculated. The present 

 species will bear no comparison with the A. Bartonii, with 

 which, nevertheless. Mr Say appears to have confounded it. 

 when he assures us that the lasl mentioned species are "ex- 

 tremely common in the pine barren marshes of the southern 

 states, and particularly in those of Georgia and Florida." 

 Vid. Journal of the Acad. Nat. Sci. Phila. Vol. I. p. 11 I.) 



All the crawfish, which I have seen from the southern 

 sinies. (and I have received specimens from New Orleans and 

 South Carolina) are of the same species with that now de- 

 seribi d. 



