THE TAIL OF A SXAKE. 177 



rattling noise which can be distinctly heard at the distance 

 of six feet. As often as the animal was irritated or surprised, 

 its tail was shaken, and its vibrations were extremely rapid. 

 This TrigonocepJialus has, therefore, in some respects the 

 structure of a viper with the habits of a rattlesnake.' 



Dr. Gijnther and Sir Joseph Fayrer both mention a 

 peculiarity of this kind in some of the Eastern representatives 

 of the (7r^/^///j", viz. the Trijncj-esuj'i^ Indian tree snakes. The 

 former writes : ' Some have prehensile tails, which, when not 

 so occupied, vibrate rapidly, producing a rustling sound 

 among the leaves.' ^ Others of the family have horny 

 tails. 



Dr. Andrew Smith, in his Zoology of South Africa, 

 mentions Vipera caiidalis especially, as having a 'tail distinctly 

 recognised, at the termination of his very thick body, and 

 which is not often seen.' In the vipers, however, more than 

 others, tails are distinguishable, those of many of them being 

 short as well as suddenly tapering to a point. The deadly 

 Puff adder is called BracJiyiira on this account, its tail 

 being extremely short for the size of the snake. One 

 exceedingly dangerous kind in St. Lucia is known as the 

 ' Rat-tailed snake.' For climbing, and as a propelling power, 

 this slender tail can be of little service. In St. Lucia is also 

 a ' Rat snake,' Crcbo or Cribo in vernacular {Spilotes 

 variabilis), one of the active non-venomous kinds which, not 

 content with rats and mice for food, wages war on its most 

 venomous fellow-reptiles; as the 'Racer' and the 'King 

 snake' do against the rattlesnake of the United States. 

 This Crcbo is a graceful, elegant creature, and on account of 



1 RcplUcs of British India. 



