182 
COLYMBIDyE. 
It will be seen, in the following pages, that the stomachs of 
the red-necked, the Sclavonian, and the eared grebes that came 
under my own examination, all contained feathers, but that those 
of the little grebe never did so. Mr. Darragh has remarked to 
me, with respect to the great-crested grebe (of which he has pre- 
served a number of specimens), that at all seasons of the year 
feathers are ready to drop out on the slightest touch ; a provision 
which we may conceive made to supply the wants of the digestive 
organs without any pain attendant on pulling the plumage from 
its body. 
As I have never seen any satisfactory reason given for the in- 
variable presence of feathers in the stomach of this species, the 
bodies of the last three birds were submitted to the examination 
of Dr. Gordon, Professor of Surgery, Queen's College, Belfast, in 
the hope that he might be able to throw some light upon the 
subject. He very kindly undertook the task, and examined a 
red-necked grebe also, obtained on the 23rd of February, 1850. 
His observations are as follow : — 
“ The proventriculus, or circle of glandules, occupying the lower end 
of the oesophagus, when opened and measured, was, in the crested grebe 
(Podiceps cristatus ), one inch six lines in the vertical, and two inches 
four lines in the transverse diameter ; whilst in the red-necked ( Podi - 
ceps rubricollis ) the vertical diameter was one inch and four lines, and 
the transverse two inches. The glandules are larger in the former than 
in the latter. 
“ The muscular coat of the gizzard is not so thick as in the Rasores , 
or gallinaceous birds, but exceeds that of the Raptores , or birds of prey, 
and is proportionally more largely developed in the crested than the 
red-necked grebes. The inner membrane or epidermic coat in both is 
nearly a line in thickness, and gradually becomes more dense and horny 
as we approach the pylorus, where it resembles that of the Gallinacece. 
The general cavity of the gizzard does not open abruptly into the small 
intestine, but forms a funnel, half an inch in length, with strong mus- 
cular walls, much constricted at its termination, so much so, indeed, as 
not to allow of the exit of at least the larger bones into the small in- 
testines. It is therefore admirably adapted for retaining its contents 
and crushing the bones and other substances which may enter it. In 
