362 THE GENUS CALLINECTES—M. J. RATHBUN. 



United States of Colombia: Sabanilla, str. Albatross (No. 18235, U. S. N. M.); 



Carthagena, Atrato Expedition, Dr. A. Schott (No. 2460, U. S. N. M.). 

 Brazil: Para, Cannavieras and Itabapuana, Thayer Expedition (Mus. Comp. 



Zool.); Maranhao, Lieut. F. E. Sawyer, U. S. N. (No. 18233, U. S. N. M.). 



The type locality of G. bocourti is Riviere de Mullins, 20 miles south 

 of Belize, Honduras j of C. cayennensis is Guiana. 



The small sterile female from Aspiiiwall <lescribed by Ordway ' doubt- 

 less belonged to this species. The specimeu, however, is not extant. 

 The only very young specimen I have examined is a female IJ inches 

 wide, in which the lateral teeth are not widely separated as in adults, 

 but their margins are in contact at base, the posterior edges of the 

 teeth considerably longer than the anterior. The median frontal teeth 

 are proportionally larger than in adults, smaller and more advanced 

 than the lateral. 



A single smaller male specimen labeled '■'■Callinectes africanus (A. M. 

 Edwards), Senegal" has lately been received from the museum at Paris. 

 Without further evidence I am not able to say that this species differs 

 from Call'mectes bocourti. The median teeth of the front are less 

 advanced than the lateral ; the lateral spine is about twice the length 

 of the adjacent tooth. Length of carapace 18.5; width 36 mm. The 

 type locality of C. africanus is Cape Verde Islands. As the range of 

 Callinectes larvatus includes these islands and the African coast, it is 

 not im]>robable that others of our American species are also found there. 



CALLINECTES ARCUATUS, Ordway. 



(Plates XX; XXIII, fig. 1; XXIV, fig. 8; XXV, fig. 7; XXVI, fig. 7; XXVII, fig. 7.) 



Callinectes arcuatus, Ordway, Boston .Journ. Nat. Hist., VII, p. 578, 1863. 

 CalUnectea pleuriticus, Ordway, Boston .Journ. Nat. Hist., VII, p. 578, 1863. 

 Callinectes arcuatus, A. Milne-Edwards, Crust. Reg. Mex., p. 228, 1879 (variety 



of Callinectes diacanthus). 

 Callinectes pleuriticus, A. Milne-Edwards, Crust. Reg. Mex., p. 228, 1879 (variety 



of Callinectes diacanthus.) 

 Callinectes duhia, Kingsley, Proc. Boston Soc. Nat. Hist., XX, p. 156, 1879. 

 Callinectes, sp., Smith, Third Ann. Kept. Peabody Acad. Sci., 1870, p. 91 (1871). 



Carapace very convex, finely granulate; granules very numerous in 

 the median region. Length of intramedial region about one-half its 

 anterior width; length greater than in C. dana\ Front with four stout, 

 triangular, blunt teeth, the middle pair about one-third the size of the 

 outer pair (Plate XXIV, fig. 8). Subfrontal spine exceeding the lateral 

 frontal teeth but little. Suborbital tooth rounded. Anterolateral 

 margin very arcuate; teeth large, well separated, those nearest the 

 orbit subacute, becoming sharp and spinous toward the lateral spine, 

 which is between two and three times the length of the adjoining tooth. 

 Penultimate segment of male abdomen broad at base; margins sub- 

 parallel for the greater part of their length (Plate XXV, fig. 7). 

 Appendages (Plate XXVI, fig. 7) reaching or nearly reaching the last 



'Boston .Journ. Nat. Hist., VII, p. 575. 



