8 PROFESSOR FLOWER ON RISSO’S DOLPHIN. 
the base of the pedicle of the arch of the sixth vertebra. This obviously represents 
the neck of the seventh rib. 
There are eight pairs of sternal ribs, the last being very rudimentary. The first pair 
articulate near the anterior extremity of the sternum, the second at the junction of the 
first and second segments of that bone, the third at the junction of the second and third 
segments, and the fourth and fifth to the hinder end of the third segment. ‘The 
remainder are not directly connected with the sternum. 
The various elements of the sternum are consolidated into a single bone, though 
traces of its original formation out of three segments can be seen, and the primordial 
median fissure is indicated by a slight longitudinal groove on its inner surface and a 
small foramen near the anterior part of the first segment or manubrium. ‘The entire 
length is 11:2 inches. The greatest breadth of the first segment is 5°5 inches; the 
least breadth, at the middle of the second segment, is 1-7 inch. The manubrium is 
very slightly notched in the middle line in front; behind the attachment of the first 
pair of sternal ribs its lateral borders expand as usual into rough triangular processes, 
directed outwards and backwards. The hinder end of the posterior segment is deeply 
notched’. 
The pelvic bones are slender and styliform, 4:9 inches in length. 
In general form the skull resembles the well-known figure of that of G. griseus in 
Cuvier’s ‘ Ossemens fossiles, pl. 225. 
In plate 54 of the great work on the osteology of the Cetacea, now in progress, by Pro- 
fessors Van Beneden and Gervais, are beautifully executed and evidently most faithfully 
drawn figures of skulls, named respectively Grampus rissoanus and Grampus griseus, from 
specimens in the collection at Paris, doubtless the type specimens’. There are certain 
obvious differences between these two figures, especially in the size of the nasal bones and 
the width and form of the rostrum; but whether these are more than individual differ- 
ences it would be hard to say, without a comparison of a large series of specimens. It 
is to be noticed, however, that in all those points in which the figures differ, the present 
specimen resembles G. griseus rather than G. rissoanus ; indeed the figure of G. griseus 
(fig. 7) is so close a representation of it, both as to form and size, that, except for a 
trifling difference in the shape of the anterior edge of the narial aperture, it might very 
well have been drawn from it. 
In the flatness and breadth of the cranial part of the skull, and the wide expansion 
of the maxille above the orbits, it much resembles that of Globicephalus; but it differs 
in the rounded form and absence of elevation of the region behind the superior narial 
apertures, in the marked convexity of the premaxille in front of these apertures, and 
' This sternum appears narrower, in proportion to its length, than that of Grampus griseus figured by Van 
Beneden and Gervais (op. cit. pl. 54. fig. 9), but otherwise does not differ materially from it. It closely 
resembles the sternum of Globicephalus. 
* Unfortunately the letterpress of this portion of the work has not yet appeared. 
