THE SrOTTED AND KINGED BOAS. 523 



but boas ordinarily do not attain more than twenty feet in 

 length. 



THE SPOTTED BOA. 



The boa scytale, or spotted boa, is of a grayish 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 approaching, — with the excep- 



