AVES. 
252 
greater number of them are also feeble flyers, and several are quite deprived of that faculty, in 
consequence of the shortness of their wings, they may be regarded as exclusively attached to the ’ 
surface of the water : their plumage is particularly dense, and its surface frequently polished, 
presenting a silvery lustre. They swim under water by the aid of their wings, which are 
employed as fins. Their gizzard is tolerably muscular ; the coeca of moderate length. They i 
have only one special muscle on each side of their lower larynx. Such are 
The Loons {Colymbus, Lin.), — 
Which are characterized by a smooth, straight, compressed, and pointed bill, with linear nostrils ; but 
require to be subdivided from characters derived from the feet [the entire skeleton, character of 
plumage, propagation, &c. &c.] 
The Grebes {Podieeps, Latham ; Colymbus, Brisson and Illiger), — 
Instead of ordinary webs between the toes, have the latter widened as in the Coots, and the anterior 
connected only at base by membranes, [which border the remainder] . The claw of the middle toe is 
flattened ; the tarsi exceedingly compressed. The semi-metallic [or satiny] 
lustre of their lower plumage has led to the occasional employment of it as 
fur. Their tibia, as also that of the Loons [in which it is much more pro- 
duced,] is prolonged forwards beyond the joint, to give a more efficient 
insertion to the extensors of the leg. [Sternum (fig. 123)* very short, 
and of peculiar conformation, approaching in some respects to that of 
the Cormorants ; which these very singular birds also resemble in the 
character of their eggs, the hard shell of which is invested with an ab- 
sorbent chalky substance. They have no vestige of a tail. The young are 
clad in exquisitely soft down, which is striped black and white, as in the 
Emeu. The constant number of cervical vertebrae is nineteen instead of 
thirteen, as in the restricted Loons ; and theh skeleton is altogether 
extremely different.] 
These birds reside in lakes and ponds, and nestle among the rushes, 
[producing numerous eggs, whereas the Loons lay very rarely more than 
two]. It appears that under certain circumstances they carry their young 
under their wings. Their size and plumage change so much with age [the 
latter rather according to season], that naturalists have very much multiplied the species. M. Meyer 
reduces those of Europe to four, [instead of five, which is the right number, as follow] : — 
The Crested Grebe (P. cristattis).— As large as a Duck, and satiny-white, with dusky upper-parts, acquiring with 
age a double black crest, and rufous collar edged with black, [which exist only during the breeding season]. 
The Red-necked Grebe (P. Smaller, with the neck bright rufous, and greyish collar less developed. 
The Horned Grebe (P. cornutus) [and Eared Grebe (P. awn^Ms).— Still less, and precisely of the same size with 
each other, so that they can only be distinguished, when the seasonal collar falls, by the beak of the second being 
distinctly a little recurved, and by a difference in the colour of the iris of the recent specimen ; their collars, how- 
ever, during the breeding season, are very different, and that of the Eared Grebe is less developed than in the | 
other]. 
The Little Grebe (P. wmor).— Size of a Quail, with never any crest or collar. [These various species, notwith- 
standing the shortness of their wings, can fly with considerable speed, when they once fairly rise, which they do || 
with unwillingness, and seldom except when compelled to migrate. They can walk with their feet, and do not .,| 
trail upon the belly, like the Loons ; and when under water, they make more use of their wings than the latter do 
habitually]. 
The Finfeet {Heliornis, Bonaterre; Podoa, Illiger) — 
Have feet lobed as in the Coots and Grebes, but their tail is more developed than in either, and 
claws sharper. ' 
Such is Plotus surinamensis, Gmelin ; and Heliornis senegalensis, Vieillot, which Gmelin approximated to the |i 
Anhingas. ^ 
The Loons {Colymbus, Latham; Mergus, Brisson; Eudytes, Illiger), — 
With all the [external] form of the Grebes, have the feet webbed in the ordinary manner ; that ill? 
to say, their three front toes are connected by membrane to the tips, and are all terminated by | 
* The representation (fig. 123), in other respects accurate, is somewhat too long. — E d. 
