AVES-BIRDS 
CONNECTION BETWEEN BIRDS AND REPTILES. 
FTER a consideration of reptilian life, which comprises the 
most dangerous and repulsive of creatures, doomed largely 
to crawl in the dust at the feet of their implacable 
foe since the gates of Eden were shut against man¬ 
kind, we approach the next order of animate crea¬ 
tion only to find a transition most remarkable, a 
true antithesis, yet connected by a chain in which 
none of the links are missing. How seemingly 
great is the chasm lying between the sinuous 
creeping, poisonous reptiles, and the bright plum- 
aged warblers, that g;o whirling through space, 
with every dip of wing a symphony of grace, 
while filling the air with a harmony that makes every 
wood musical, and every hedge an orchestra. How great 
the difference between the scale of the saurian and the 
gossamer, sun-tinted feather of the bird; or the threaten¬ 
ing hiss, croak or bellow of one, and the lute-like notes, the piping trill of woodland 
eloquence flooding the very world with melody, that is flung with generous praise 
from the throat of the other! Though these may be ever so widely divergent, 
the lines of separation are like an acute angle, the ends of which are far apart 
but converge again to a common centre. 
The characteristic features by which the three great divisions of animals, 
viz., reptiles, birds and mammals, are distinguished, are scales, feathers and hairs. 
Other points of difference exist in that feathered creatures possess a double circu¬ 
lation of the blood, which is single in reptiles, while the absence of a diaphragm 
and mammary glands, as well as the possession of a second stomach, the crop, a 
grinding organ and the gizzard, serve to separate birds from mammals. This 
separation from mammals is very much more distinct than are the character¬ 
istics which divide birds from reptiles. While the differences are strongly 
marked, there still remain several homologies that serve to unite birds with 
reptiles. In speaking of these connecting links, the English naturalist, Kingsley, 
thus writes: 
u * * * In these and other particulars, the birds show a near relation¬ 
ship to reptiles, so close, indeed, that they have been included with them in a 
separate group, called sauropsida; at any rate, birds are more nearly related to 
reptiles than they are to mammals, notwithstanding the beak of the duck-mole 
and the recent re-discovery of the fact that the echidna (porcupine ant-eater) lays 
eggs, and whatever was the origin of mammals, so much is certain, that they 
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