25^ CLASS REPTILIA. 



not, in which the upper part of the body and of 

 the tail is furnished with transverse scaly bands of a 

 single piece, and which have neither spur nor rattle 

 at the end of the tail. As they are very numerous, 

 independently of the subtraction of the venomous 

 species, the others have been again subdivided. 



The Boas, more especially so named, have a 

 crook on each side of the anus. The body is com- 

 pressed, more bulky towards the middle, the tail 

 prehensile, and the scales small, at least, on the 

 posterior part of the head. Amongst them are found 

 the largest of all the serpent tribe. Certain species 

 attain the length of thirty and forty feet or more, 

 and can swallow dogs, deer, and even oxen, accord- 

 ing to the report of some travellers, after having 

 crushed them between their folds, covered them 

 with their saliva, and enormously dilated the jaws 

 and throat. This operation is very long. A re- 

 markable circumstance in their anatomy is that 

 their small lung is only one-half shorter than the 

 other. 



These serpents are again subdivided, according to 

 the teguments of their head and jaws. 



1. Some have the head covered as far as the end 

 of the muzzle, with small scales similar to those of 



adder with four stripes, or of the serpent of Epidaurus, among the Latins. 

 Pliny says, that they were thus named because they sucked the udder of 

 cows. The boa, one hundred and twenty feet in length, which it was 

 pretended was killed in Africa by the array of ReguUis, was probably a 

 python. 



