if '^y 



NOTES ON THE WEST INDIAN " FER-DE-LANCE." 



Dr. WILLIAM DUNCAN. 



Read February 1th, 1889. 



THE Fer-de-lance belongs to tlie family Crotalidm, or Pit 

 "Vipers, of which perhaps the best known member is 

 the Rattlesnake. The Crotalidce. are distinguished from 

 the true vipers {Viperidce) by a pit in the loreal region be- 

 tween the nostrils and the eye. These two families con- 

 stitute the sub-order Opliidii Vlperlformes, the fourth of the 

 four sub-orders into which the snakes or ophidii are divided 

 by modern zoologists. They are characterized by the tri- 

 angular head and short tail and by the very short maxillary^ 

 or upper jaw bone, which bears a single long perforate 

 poison fang (although there may be several reserve fangs). 

 The maxillary is capable of rotation on its transverse axis, 

 and this rotation causes the erection of the tooth when the 

 mouth is wide agape. Small hooked, solid teeth are pre- 

 sent in the lower jaw and palate. 



The Eer-de-lance belongs to the genus Trigonoceplialus 

 {Craspedoceplialus of some authors) of which there are 

 three species, T. jararaca and T. atrox, which are common 

 in Brazil, Central America, and Jamaica, and T. lanceolatus 



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