NATURAL HISTORY OF SELBORNE. 
443 
Moral. 
Good gentlemen all, both great folks and small, 
This hint accept kindly from me, 
We want evidence clear ! don't believe all you hear. 
And not more than half that you see, see, see 
And not more tlian half that you see. 
Henry Lee. 
Holland, the keeper of the snakes, tells me that vipers under 
his charge at the Zoological Gardens often have young in 
their glass dens. The vipers that have had young are the 
Russell viper, black water viper, and the common viper. In 
no instances have any of these vipers attempted to siualloiv their 
young alive. Snakes frequently swallow each other when they 
have had hold of the same frog, and the swallowee has to be 
shaken out of the gullet of the swallower. Mr. Bartlett once 
made a boa-constrictor take a full meal in a very ingenious way. 
Boas, as is well known, will never seize an animal which is 
dead. The boa in question had not fed for many weeks. At 
last he seized a live rabbit, killed it by crushing, and swallowed 
it. Just as the rabbit was disappearing down the snake's mouth, 
Mr. Bartlett tied another dead rabbit to the legs of the one 
being swallowed, then another on to that. The snake must 
have thought that he had got hold of a tremendous long rabbit. 
In the summer of 1875, my friend Mr. Burr forwarded 
me a small viper alive, with the mouse he disgorged when 
captured. His under-keeper caught him, and observing that 
he was very large in the middle, thought he had some ailment. 
SKIN OF vip?:r. 
but on handling him he brought up the mouse, which is very 
much larger in girth than he is. The viper measures about 
ten inches, and is about the size of a common Severn lamprey. 
The mouse was a field-mouse, and about the size of a three- 
