4. DELPlIliNUb D. LONGIROSTRIS. 161 



the total length; pectoral fins about three times as long as broad, nar- 

 row in the distal half, and obtusely pointed. 



Form and disposition of color markings very variable. Back, upper 

 jaw, tail, and fins black or dark gray; under parts white or greenish- 

 white. Tlie black area extends down upon the sides under the dorsal 

 fin in the form of an angular projection (sometimes indistinct), the apex 

 of which is met by the apex of a similar upward projection of the 

 white of the under parts. Sides occupied by two elongated ellijitical 

 areas of light color, the anterior and larger of which is fulvous in some 

 individuals and gray in others; the i>osterior area is gray. A black, 

 gray, or greenish band extends from the lower jaw to the base of the 

 pectoral fin (sometimes absent). Eye surrounded by a ring of black, 

 from which a narrow black band extends forward to the base of the 

 beak. End and margin of lower jaw usually black. One or two longi- 

 tudinal bands of gray or greenish-gray traverse Uie light color of the 

 lower part of the sides. 



Teeth f^ to f J. A^ertebra;: C. 7; D. 14(-15) ; L. 21(-22) ; Ca. 30 

 (-32) = 73(-7G). Rostrum depressed and elongated, its length exceed- 

 ing one-balf the total length {'iS per cent, to Gi per cent.). Premaxilhe 

 convex, anchylosed together in the median line. Proximal fifth of the 

 palatal ridge with nearly parallel margins, its sides excavated by the 

 lateral grooves. Pterygoid bones sharply keeled. Vomer appearing 

 in the median line of the palate as a linear slip. Temporal foss;e 

 elongated, their length a little more than one-sixth the total length of 

 the skull. 



Measurements of the exterior. — S (21524 U. S. National Museum. 

 Wood's Holl,Mass.). Total length, 89 inches (220.1'^'") ; end of beak to 

 dorsal fin, 39.3 inches (99.8'='"); to pectoral fin, 20.0 inches (50.8'='") ; 

 vertical height of dorsal fin, 9.0 inches (22.9'"") ; length of pectoral fin, 

 14 inches (35.6"^^'"); breadth of flukes, 20.5 inches (52.1'"'). 



Measurements of the sJcull. — (20873 U. S. National JMuseum. Block Isl- 

 and, R. I. See p. 48.) Total length, 40.7'"'; length of rostrum, 28.2'="^; 

 breadth of rostrum at its base, 9.3""; at its middle, 5.3'"' ; breadth 

 between orbits, 17.1'='" ; length of temporal fossa, 7.2<"'. 



Sahitat. — Pelagic. 



DELPHINUS LONGIROSTRIS Cuvier. 

 (Plato 12, fig. 2.) 



External characters unknown. 



Teeth ^g- Rostrum of skull greatly elongated (G7.9 per cent, of the 

 total length) ; its breadth at the maxillary notches one-fourth its 

 length. Length of the symphysis of the mandible one-fifth the length 

 of the skull. Temporal foss?e large and rounded. Palatal grooves and 

 ridge as in J), delphis. 



Measurements of the skull. — (Type.) Total length, 19.5'='" ; length of 

 18378— Bull. 3G 11 



