ON THE 
NATURAL HISTORY AND CLASSIFICATION 
OF 
BIRDS. 
PART III. conrinveEp. 
ON THE NATURAL HISTORY AND RELATIONS OF THE 
DIFFERENT ORDERS, TRIBES, AND FAMILIES OF 
BIRDS. 
CHAPTER III. 
ON THE DENTIROSTRAL ORDER, THE LANIADA, OR SHRIKES. 
-(1.) Tus conclusion of our last volume terminated our 
exposition of the relations of the Dentirostral Order. 
Our chief reason for entering so fully into that exposition, 
as we then stated, was to substantiate the three leading 
principles upon which (as we maintained) the system of 
nature is founded ; namely, 1. The circular progress of 
affinities ; 2. The theory of representation, by which the 
contents of one group analogically represent the con- 
tents of all other groups ; and, 3. The definite nature of 
the principal types, contained in every circle. These 
are the chief propositions with which we commenced 
our exposition of the whole animal kingdom *, and which 
* Classification of Animals, 241. 
VOL. Il. B 
d > 
e ‘i vd 
