298 
BIRD-LIFE. 
seen together on the “playing-ground” of the former, 
and the fact proved beyond a doubt. Mule birds have 
also been observed among the different species of Indian 
Jungle-fowl; between Black Game and Willow Grouse; 
between the Carrion and the Hooded Crow; House and 
Tree Sparrow; as also between several various species 
of Ducks, &c. Of many cases, however, which have been 
reported we need proofs. “ The actions of animals in a 
state of captivity,” says Homeyer, “ can in nowise serve 
as conclusive evidence, for the reason that they are 
surrounded by conditions of life which are wholly and 
totally artificial, and thus one would judge of nature 
from what is unnatural.” 
In confinement such mesalliances often occur among 
birds, and this has also taken place between creatures 
differing widely from one another; yet one cannot, in 
any way, assume from these accidents that the great 
variety of the bird world is to be mainly attributed 
to the crossing of opposite species. From what has 
gone before, it is highly improbable that creatures with 
whom the conjugal bond is so faithfully respected should 
take especial pleasure in passing the bounds of nature. 
We are too well acquainted with birds and their habits 
not to be able and willing to defend them against the 
charge of infidelity in general, where exceptions only 
rarely occur. 
