THE SPOTTED AND lilNGED BOAS. 523 



Imt boas ordinarily do not attain more than twenty feet in 



iengtli. 



THE SPOTTED BOA. 



The boa scytale, or spotted boa, is of a gi^ayish colour, 

 marked with round spots, and scarcely inferior in size to the 

 former. 



THE RINGED BOA. 



There is another species — the ringed boa, or boa cenchris — 

 which, though growing to a considerable size, does not attain 

 that of the former species. 



A curious species (the boa canina) has a large head, shaped 

 somewhat like that of a dog ; the general colour a bright 

 Saxon-green, with transverse white bars down the back. The 

 sides are of a deeper green, and the belly is white. 



Wallace describes a small one only eleven feet in length, 

 but as thick as a man's thigh. It was secured by having a 

 stick tightly tied round the neck. It went about dragging 

 its clog with it, sometimes opening its mouth with a very 

 suspicious yawn, and sometimes turning its tail up into the 

 air. Being put into a cage, and released from the stick, it 

 began to breathe most violently, the expirations sounding like 

 high-pressure steam escaping from a Great Western locomo- 

 tive. 



- The boa, however, is not much dreaded in South America, 

 as it seldom or never attacks man ; which the anaconda is said 

 always to do, if it can find him unprepared. Stories are told 

 of desperate encounters between travellers in the forests of the 

 Amazon and pythons or boas. A French traveller narrates 

 how, on one occasion, the whole of his attendants took to 

 flight on seeing a huge python ajjpruaching, — with the excep- 



