398 KEPORT OF THE COMMISSIONER OF FISHERIES. 



Callinectes haatatus Onlway, JNIonngraph of the Genus Callinectes, Boston Journal 

 Natural History, Vol. VII, 1863, p. 568-579. 



Verrill, Invertebrates of Vineyard Sound, Report U. S. Fish Com- 

 mission 1871-72, 1873; contains a number of references, but 

 none of great importance. 



S. I. Smith, in Verrill, Invertebrates of Vineyard Sound, Report 

 U. S. Fish Commission 1871-72, p. 548, 1873. 



Milne-Edwards, Crustaces de la Region Mexicaine, p. 224, 1879. 



Faxon, On Some Crustacean Deformities, Bulletin Museum Com- 

 parative Zoology, Vol. VIII, 1881, pi. ii, figs. 5 and 8. 



Conn, Johns Hopkins University Circular, November, 1883. 



R. Rathbun, Fisheries and Fishery Industries of the United 

 States, Section I, History of A(j[uatic Animals, pp. 775-778, pi. 

 267, 1884; Section V, Vol. II, History and Methods of the 

 Fisheries, pp. 629-648, 1887. 



H. M. Smith, Notes on the Crab Fishery of Crisfield, Md., Bulletin 

 U. S. Fish Commission, IX, 1889, p. 104, 1891. 



Paulmier, The Edible Crab, a preliminary Study of Its Life His- 

 tory and Economic Relationships, 55th Annual Report N. Y. 

 State Museum, 1901, pp. rl29-rl38. The Crab Fisheries of 

 Long Island, 56th Annual Report of the N. Y. State Museum, 

 1902, pp. rl31-rl34. 

 CaUiiiecies scqndus M. J. Rathbun, The Genus Callinectes, Proceedings U. S. 

 National Museum, Vol. XVIII, 1895, pp. 352, 366-373. The 

 Cyclometopous or Cancroid Crabs of North America, American 

 Naturalist, Vol. XXXIV, February, 1900, p. 140. 



Bouvier, Bulletin Musee Paris, VII, 1901, p. 16. 



SYSTEMATIC POSITION. 



The blue crab ( Callinectes sajrichis Rathbun) is a common and well- 

 known crustacean along the Middle and South Atlantic and Gulf 

 coasts of North America. It is one of the nine species which in Miss 

 Rathbun's recent revision" are regarded as forming the genus, the 

 other members of which are inhabitants of the coasts of South America, 

 Mexico (on both the Atlantic and Pacific sides), and the Atlantic coast 

 of Africa. Callinectes is one of the genera constituting the family 

 Porti/7iidce, the members of which are commonly known as "swim- 

 ming crabs," from the fact that with one exception in all the known 

 species the last pair of legs are developed as broad paddles by means 

 of which the animals propel themselves through the water. The 

 family is an extensive one, but those genera which occur on the coasts 

 of North America may be readily distinguished by the following key, 

 which is adapted from Miss Rathbun : * 



o. Last pair of legs broad, modified into swinuning paddles. 

 b. Carapace decidedly broader than long, antero-lateKal margins cut into nine teeth. 



a The Genus Callinectes, Mary J. Rathbun, Proc. U. S. Nat. Mus., XVIII, 1896, 

 pp. 349-375, pis. xii-xxviii. 



i^ Synopses of North American Invertebrates, American Naturalist, XXXIV, Feb., 

 1900, p. 139. 



