176 M. F. Cuvier De VHistoire 
which this circumstance does not so readily explain, which may be 
characterized under the name of innovation, and which assuredly 
should not have been employed to the extent it has been, without 
some very urgent and pressing necessity. In many particulars, in- 
deed, M. Cuvier manifests a becoming respect towards the decisions 
of his illustrious brother, but in not a few instances he treats his 
opinions with as little ceremony as he does those of others, and re- 
jects his proposals, and substitutes other -views, which of course he 
regards as preferable. Thus, whilst he follows the new and admi- 
rable arrangement of the Baron with regard to the herbivorous Ce- 
tacea, and to the great whales, he very much forsakes and opposes 
him, and so innovates, in reference to that very numerous group 
which is intermediate between these two extremes. There can be 
little doubt that this is now the most perplexed and difficult 
part of the subject, and in illustration of the statement just made, 
and still more, as bearing very essentially on the future progress of 
the science, we judge it right to dwell somewhat more at large on 
the point. 
IVIost of our readers are probably aware that some progress has 
been made in classifying these unnumbered, not to say innumerable 
species of smaller Cetacea. In the time of Bonnaterre, not fifty years 
ago, the genus Delphinus contained only nine species, but since that 
period this number has so much augmented, and is still so rapidly 
increasing, that it has long been felt necessary to break it up and 
subdivide it. It was the illustrious Lacepede who led the way in 
this division by the introduction of his Delphinapterus, including 
those which had no dorsal fin. Rafinesque Smaltz folio wed, by his 
discovering a species with two dorsal fins, which he named oxypte- 
rus. Baron Cuvier introduced a distinction founded upon what we 
may call the facial line of the living animal, thus separating the 
Phoccena, whose head and snout are uniformly curved to the ex- 
tremity, from the Delphinus, which has a distinct fall or groove be- 
tween the forehead and beak. Pursuing the same idea, Blainville 
introduced the Delphinorhyncus , which has a beak, which separates 
it from the phocenae, and yet the beak not distinguished from the 
forehead, as in the dolphins, but on a uniform slope from the top 
of the head to the extreme point ; and finally, Lesson has proposed 
to constitute the Globiceps, whose heads are almost wholly rounded 
like a globe, into a genus. Now these proposals have all, more or 
less, been adopted, and most of them, as the Delphinapterus, Del- 
phinus, Delphinorhyncus, Phocsena, universally by later writers, 
such as Desmarest, Cuvier, Scoresbv, Blainville, Lesson, c. An- 
