TKIGONOCEPHALUS CONTORTRIX. 71 



there were 150 abdominal plates, 42 subcaudal, and four pairs of bifid plates or 

 scales near the apex. 



Habits. The Trigonocephalies chooses dark and shady places for its residence 

 in general, though at times it is found in meadows of high grass. Its usual food 

 seems to be small birds and field mice, which I have more than once found in its 

 stomach. In confinement they could never be made to take any food; though 

 different small animals were offered, they would kill, but never eat them. 



Geographical Distribution. The Trigonocephaly contortrix, has an extended 

 geographical range. I have received them from the western parts of New 

 England to middle Florida, inclusive, and from the shores of the Atlantic to the 

 borders of the Alleghany mountains. As yet, I have no evidence of its existence 

 in the valley of the Mississippi; its place is there probably supplied by the 

 Toxicophis atro-fuscus of Troost, to which its habits are very similar. 



General Remarks. This animal was first described by Linnaeus in the twelfth 

 edition of his Systema Naturae, under the name Boa contortrix, and it ranges well 

 under his genus Boa, which included all those serpents, venomous or not, that had 

 plates under the tail, as well as on the abdomen. The specimen from which he 

 took his description, was sent him by Dr. Garden, and had, according to his 

 account, the same number of plates as the animal here described, though he does 

 not mention the two or three scales or bifid plates on the tail. He says further- 

 more that he found the gland or sac for containing the venom, but that there were 

 no fangs, which might have been the result of accident, as the larger fall out and 

 are succeeded by others. It cannot be imagined why he should have given a 

 reference to the hog nose of Catesby,* especially as this is far removed from his 

 genus Boa, in having scales or bifid plates under the tail. This reference to the 

 Coluber constrictor of the tenth edition of the Systema Naturae, which is a very 

 different animal from that of the twelfth edition, is still more remarkable, as it 



* Cates., Carol., &c, vol. ii. pi. lvi. 



