C E T A C E A. 



27 



3. Order CETACEA.— The Aquatic Mammals. 



1. Family DELPHINIDiE— The Dolphins. The Porpoises. 

 1, Genus DELPHINUS, Linn. Syst. Nat. I, p. 108 (1766). The Dolphins. 



1. Delphinus obscurus, Gray. Spic. Zool. p. 2 (1828). 



Delpldnus cruclger, QuoY and Gaim. Voy. Uranie, Zool. p. 87 (1821) ? 

 Delphinus hivittatus,JjY.ssON, Voy. Coquille Zool. I, p. 178 (1826)? 

 Dblpliinun fitzroyii, Waterhouse, Voy. Beagle, Mamm. p. 25 (1840). 

 PJioccena australis, Peale, Zool. Exp. Exp. Mamui. p. 33 (1848). 



Atlas, Mammalogy, Plate Y, Fig. 1. 



Yoj. Beagle, Mamm. Plate X; Voy. Coquille, Mamm. Plate IX? 

 Voy. Uranie, Mamm. Plate XI ? 



This species, which appears to be an abundant animal of the coasts 

 of South America, is stated by Mr. Peale to have been " harpooned 

 in the South Atlantic Ocean, ofi the coast of Patagonia, on the 12th 

 of February." It appears to be liable to very considerable variation 

 of colors, or rather of the distribution and extent of the white color of 

 the under parts, and, consequently, of the dark of the upper parts also. 

 It has been frequently described by authors, and its correct nomen- 

 clature and synonymy would not, we think, be ascertained without 

 some difficulty and very considerable expenditure of time. 



Mr. Peale's description is as follows : 



"Snout, back, and all the fins, dark slate-color; sides, paler or 

 gray, a white lateral line commences opposite the posterior edge of 

 the dorsal fin and reaches the tail; beneath white, which joins the 

 gray of the sides by an undulated line. 



" Total length, seven feet ; greater diameter, opposite the dorsal 

 fin, eighteen inches ; pectoral fin, sixteen inches ; dorsal fin, seventeen 

 inches ; across the tail, twenty inches. 



" Dental formula : |>, H, = 120." 



IIab. — South Atlantic Ocean, Coast of Patasronia. 



