240 DR. J. MURIE ON THE ORGANIZATION OF THE CAAING WHALE. 
of the cranium and its superincumbent nodosity. The under surface of the chin deepens 
towards the throat; and the contour from this point ventrally towards the tail is a 
nearly uniform, narrowing, sweeping line. The dorsal antero-posterior curve almost 
corresponds to the abdominal one, excepting where interrupted by the back-fin. To- 
wards the caudal extremity the perpendicular depth is but moderate. Opposite the 
dorsal fin the body insensibly narrows, which narrowing steadily increases the nearer it 
approaches the root of the caudal fin, and becomes laterally compressed. 
The subjoined measurements of our female give the relative total length in a straight 
line, and curvilinearly following the dorsal arch, in distances between various points. 
From these data it follows that the amount of arching of the back and projecting mass 
of the snout is longer by about one foot and a half than is the body taken in a hori- 
zontal parallel straight line. 
ft. in. 
Length from the snout to the fork of the tail. . . . . . - . . 1010 
Distance from the projecting upper lip to the blow-hole, following curve 1 11 
From the blow-hole to the anterior root of the dorsal fin. . . . . 2 9% 
Dorsal fin in length at its base as Saale 1 oF 
Distance from the posterior root of dorsal fin to tail’ STOO, (oe et ae eee 
Tail from root to fork 1 
The dorsal fin is a prominent feature in the profile outline of the animal. It is large. 
falcate-shaped, and very much laterally compressed near and at its upper free margin. 
The anterior upper smooth border forms the segment of a wide arch whose summit is 
perpendicular to the posterior attached root of the fin. Behind, it terminates in an 
almost hook-like manner. ‘he posterior inferior border is deeply emarginate. This 
fin is situated in front of the middle of the body. Measured from the centre of the fin 
itself, the distance between it and the front of the truncated snout is six inches less 
than from the same point backwards to the root of the tail, while it is eighteen inches 
less when the measurement is carried to the fork of the tail-fin. 
The dimensions of the dorsal fin are:—greatest length or that continuous with the 
upper curved border to the hooked tip, 2 feet 13 inch; length of the base in a straight 
line, 1 foot 94 inches; greatest vertical height, 84 inches 
In relation to the body, the low-set position, and the peculiarly narrow, tapering, 
scythe-shape of the pectoral fins, in centrast with the blunt globose snout, render the 
Pilot Whale at once as remarkable as it is characteristic among the Cetacea. Each 
pectoral extremity or fin is thin and knife-like on the edges. The length, taken in a 
straight line, is 1 foot 103 inches; but the measurement following the curve of the 
anterior border equals 2 feet 53 inches, whereas the posterior border in its curve is only 
1 foot 64 inches. Their position is about the posterior third of the distance between 
the snout and the anterior end of the dorsal fin. 
In shape the tail seems uncommonly like that of the Porpoise. It nevertheless 
