398 REPORT OF THE COMMISSIONER OF FISHERIES. 
Callinectes hastatus Ordway, Monograph 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, Crustacés de la Région Mexicaine, p. 224, 1879. 
Faxon, On Some Crustacean Deformities, Bulletin Museum Com- 
parative Zoology, Vol. VI1I, 1881, pl. 1, 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 Aquatic Animals, pp. 775-778, pl. 
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. r129-r138. The Crab Wigtreriee of 
Long Island, 56th Annual Report of the N. Y. State Museum, 
1902, pp. rl31—r134. 
Callinectes sapidus M. J. Rathbun, The Genus Callinectes, Proceedings U. S. 
National Museum, Vol. XVIII, 1895, pp. 352, 366-373. The 
Cyclometopous or Canecroid 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 sapidus 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 
Portunide, 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:? 
a. Last pair of legs broad, modified into swimming paddles. 
b. Carapace dee udeay broader than long, antero-lateral margins cut into nine teeth. 
«The Genus Giiiaecres Mary J. R: aa Proc. U. § S. Nat. Mus., XVII, 1996, 
pp. 349-375, pls. x11-X XVIII. 
» Synopses of North American Invertebrates, American Naturalist, XXXIV, Feb., 
1900, p. 139. 
