INTRODUCTION. XV 
the light of a table of references to other works, which it 
would be therefore needless to mention. 
Such remarks as appeared strictly necessary to the eluci- 
dation of the several orders and genera, have been given un- 
der the characters of each, as they occurred in the course of 
classification ; which, it is hoped, will not be found useless, 
as being more explanatory of the grounds upon which such 
general distinctions have been established. With respect to 
the systematic arrangement, it happened, fortunately for the 
present work, that the second edition of Trmmincx’s Ma- 
nuel (containing a ‘¢ Systematic Analysis of General Ornitho- 
logy”) appeared about the time it was first contemplated ; 
and as his arrangement seemed to excel both in perspicuity 
and in sound and enlarged views of the subject, and has re- 
ceived the approbation of the most eminent naturalists, I 
considered it fully entitled to adoption; venturing, at the 
same time, to differ in a few instances, which do not interfere 
with the principles upon which his classification rests. Thus, 
I have united his two orders /nsectivores and Granivores, 
giving to such union the old name of Passerine, but separa- 
ting it mto two divisions, correspondent to the titles of his 
two orders. I have also exclusively applied the term Jnsec- 
tivorous to the Swallow tribe (as included in his order Che- 
lidones), a term better expressive of the nature of their food 
than his order Insectivores, which contains several genera not 
restricted to that particular diet. Two additional genera have 
been also established, by the separation of the Common Wren 
and the Gold-crested Wren from the genus Sylvia, making 
them the types of the genera T’roglodytes and Regulus ; but 
such an alteration has not been attempted without the sanc- 
tion of ornithologists of high authority. 
