I 
/ 
PREFACE. 
The principal object of the present Publi- 
cation being detailed in its title, any further explanation 
may be deemed unnecessary, unless to say that it is the in- 
tention of the Author, in a subsequent part of the work, 
to give a Physiological History of the Eggs, with the 
progress of incubation^ from its commencement till the 
developement of the young Bird, being the result of 
experiments instituted for the express purpose of gaining 
information on this interesting department of Animal 
Economy. 
V 
It will be observed, that in many instances, the individual 
eggs differ considerably from others of the same species, in 
such cases there will generally be given more than one 
figure. 
As a large proportion of the Birds resorting occasionally 
to this country, are not known to breed here, the Author 
has been under the necessity of depending on the kindness 
and accuracy of his friends in other countries, from whom 
he has received valuable communications; but unwilling to 
figure any species of whose identity he is in doubt, he has 
not availed himself of these communications in this part of 
the work, as he trusts that future experience will either 
confirm the present opinion of the identity of each speciej?^ 
or remove the errors that have unavoidably crept into works 
of this nature 
