170 ON SYSTEMATIC ZOOLOGY. 
investigation of nature,” who would otherwise have 
shrunk from those obstacles which he removed. 
(221.) The system of Cuvier succeeded that of Lin- 
neus, and equally embraced the whole animal kingdom. 
The immense increase that had been now made to our 
knowledge of natural productions called for the insti- 
tution of new genera and subdivisions, and a general 
revision of all the groups. Patronised by his govern- 
ment, and gifted with talents of no common order, 
this illustrious anatomist conceived the idea of a natural 
system, founded exclusively upon the organisation of 
animals. The attempt, however grand, has been emi- 
nently unsuccessful. Like all those which have been 
built on one set of characters, the system of M. Cuvier 
has eventually become most palpably artificial. But as 
we shall have frequent occasion to illustrate this opinion, 
we proceed at once to give a general outline of the great 
divisions of the animal kingdom as proposed in the 
Réegne Animal. 
(222.) In the Cuvierian system all animals are ar- 
ranged under four principal divisions: —I. Vertebrated 
animals (Animalia vertebrata). I1. Soft or molluscous 
animals (Animalia mollusca). III. Articulated ani- 
mals (Animalia articulata). And, lastly, 1V. Radiated 
animals (Animalia radiata). The principal groups into 
which each of these classes are next divided will be seen 
by the following tables. 
(223.) I. The Verresrara, or vertebrated class, are 
also divided into four groups; namely, 1. Mammalia, or 
(uadrupeds; 2. Aves, or Birds ; 3. Reptilia, or Reptiles ; 
and, 4. Pisces, or Fishes. These animals in themselves 
are abundantly different in their external form; but, as 
our author’s system professes to be founded on anato- 
mical structure only, he rejects the more plain and ob- 
vious characters, which every one can see, and which had 
been so happily employed by Linneus, and makes the dif- 
ferences between these groups to depend upon circum- 
stances which no one but an anatomist can understand. 
Thus Quadrupeds, or Mammalia, are to be known by 
