50 
REVIEWS. 
In the preface we are informed by the editor that he “has endea¬ 
voured to preserve as much as possible of the original work, and also to 
maintain and follow ont the author’s mode of treatment in those parts 
which required alteration. Changes have been introduced only when 
they appeared to he imperatively called for; and in some instances, 
where a difference of opinion still exists in the minds of zoologists, the 
original statements of the author have been retained, even when opposed 
to the Editor’s own views.” Yarious changes will consequently he 
found scattered throughout the present volume. Thus the Dodo is trans¬ 
ferred from the Cursores to theColumhse, in accordance with the opinions 
of Strickland and Melville on this remarkable bird. The separation of 
the Batrachia from the Reptiles, and the division of the latter into four 
orders, is likewise an improvement. The classification of other groups, 
e. g. the Carnivora, is different from that adopted in the first edition; 
the Hyena, Badger, and Cercoleptus, being each made the type of sepa¬ 
rate families. Other minor changes have been introduced. 
In a few instances the space devoted to the description of some of 
the more remarkable animals is, perhaps, too restricted. Thus the 
Proteus is dismissed in less than two lines. Again, the statement that 
the Hyperoodon is a rare visitant to our coasts is hardly reconcileable 
with the numerous accounts given of its appearance during the past few 
years. We do not, however, attach too much importance to these and 
other trifling inaccuracies, which seldom occur, and detract but little 
from the general merits of the work. 
We had expected that some allusion would have been made to 
Professor Owen’s recent classification of the Mammalia, a brief explana¬ 
tion of which would have added considerably to the merits of Dr. Car¬ 
penter’s book. In this respect we have been much disappointed. 
The subject is in itself so interesting that we propose laying a short ac¬ 
count of it before our readers. 
It is well known that among the extensive range of subjects which 
has occupied the attention of our most eminent comparative anatomist, 
the classification of the Mammalia has long held a prominent place. 
The numerous opportunities afforded him of ascertaining by dissection 
the anatomical characters of many of the rarer and more remarkable 
mammals which have died at the Gardens of the Zoological Society, 
have enabled him to accumulate a mass of evidence of considerable im¬ 
portance in the decision of doubtful questions, and for the confirmation 
of opinions previously untenable for want of such testimony. 
The external characters by which the Mammalia are distinguished 
from the other Yertebrata are sufficiently obvious, and need not detain 
us here. Not quite so remarkable, though equally characteristic, are those 
derived from an examination of the viscera and the organs of digestion, 
circulation, respiration, &c. Thus Professor Owen has shown that “ the 
sacro-median artery, which in some long-tailed mammals assumes the 
character of the continued trunk of the aorta, never distributes arteries 
to the kidneys or The legs, as in birds,” &c., &c. 
The osseous system presents, likewise, its own peculiarities, such as 
