PROFESSOR FLOWER ON RISSO’S DOLPHIN. 21 
Skull. Rostrum and cranium proper of nearly equal length. Upper surface of rostrum 
very broad and flat’, rounded in front. ‘The premaxille at the middle of the rostrum 
as wide as, or wider than, at the base, and very nearly or completely concealing the 
maxillz in the anterior half of the rostrum. Upper surface of the premaxille in front 
of the narial apertures strongly concave. Upper surface of the skull behind the narial 
apertures raised into a strong prominence, of which the nasal bones form the apex. 
Manus very long and pointed, the number of phalanges (including the metacarpals) 
in the different digits being respectively I. 3-4, II. 13-14, III. 10, IV. 3, V. 1. 
Grampus.—Teeth, none in the upper jaw. In the mandible 3 to 7 on each side, 
confined to the anterior part of the ramus close to the symphysis. 
Vertebre. C. 7, D. 12, L. 19, C. 30, total 68. 
Skull. Rostrum slightly shorter than cranium proper, its upper surface moderately 
broad and flat, slightly expanding laterally in front of the notch, then tapering gradually 
to the apex. The premaxille not so wide at the middle of the rostrum as at the base. 
Upper surface of the premaxille in front of the narial apertures convex. Upper 
surface of the skull behind the nasal apertures rounded. 
Manus long and pointed, the number of phalanges (including metacarpals) in the 
different digits being I. 2, II. 10, III. 8, IV. 3, V. 1. 
DESCRIPTION OF THE PLATES. 
PLATE I. 
Fig. 1. Adult female Risso’s Dolphin, caught near the Eddystone Lighthouse, February 
28th, 1870. 
Fig. 2. Upper surface of the head of the same. 
Fig. 3. Upper view of the tail of the same. 
From drawings by Mr. R. W. Sherwin. 
Fig. 4. Very young female Risso’s Dolphin, bought in Billingsgate Market, March 30th, 
1870. 
From a drawing by Mr. E. Gerrard, jun. 
All +s the natural size. 
PLATE II. 
Fig. 1. Side view of the skeleton of the adult Risso’s Dolphin. 
Fig. 2. Upper view of the same skeleton. 
1 
2 
Fig. 3. The sternum of the same, from below. 
Fig. 4. Skull of the young animal. 
All } the natural size. 
* In the skulls of very young animals these special characteristics of the genus are but slightly developed, the 
rostrum being much more narrow in proportion to its length than in adults. 
VOL. VIIIL—PART I. March, 1872. E 
