The Opisthoglyph Snakes of North America 



inoffensive species, or its mcoTbers designated as "suspects" 

 owing to tile presence of elongated, grooved teeth in the rear 

 portion of the upper jaw. It should be understood that the 

 Opisthoglyph snal<es are disiinctly poisonous. The grooved teeth 

 are poison-conducting jangs, and connect with glands in the rear 

 portion of the head. The fangs are ordinarily employed — as 

 is the venom apparatus of all serpents — to subdue and to kill the 

 prey, and not to use as weapons of aggression upon mankind. 



The majority of these snakes are but mildly poisonous and 

 consequentl)' not dangerous to man in the effects of their bites. 

 JVloreover, if biting in self-defence, they do not generally employ 

 their fangs as it is difficult for them to produce a wound with the 

 venom-conducting teeth unless they take deliberate hold and 

 advance the jaws in the familiar, chewing motion of snakes, thus 

 bringing the grooved teeth into a position to be imbedded. Few 

 snakes, unless grasped by the body, will use their jaws in this 

 fashion. If cornered, they simply "strike." As the Opis- 

 thoglyph snakes are timid and active, accidents from them are 

 very rare. However, persons have been bitten by these snakes, 

 yet escaped being wounded by the fangs. Such observers have 

 emphatically asserted that such snakes are innocuous and have 

 thus set down their views in literature. There has consequently 

 arisen a tangled argument about these creatures. 



An examination of the teeth and a dissection of the head will 

 remove all doubt as to the poisonous character of any of the 

 species. The venom apparatus is, in fact, fully as perfect — 

 though rather in miniature — as that of the much dreaded viperine 

 snakes, but in place of the fangs being perforated and ejecting 

 their venom from an orifice at the tip, they are grooved from the 

 base to the tip. The accompanying figures, illustrating the struc- 

 ture of the fangs of various snakes, demonstrate the quite dif- 

 ferent dentition of these serpents from the better-known poison- 

 ous reptiles. 



Though the writer has stated that most of the species oc- 

 curring in North America are not liable to produce injuries 

 actually formidable to man, wounds from the fangs of snakes 

 belonging to the genera Sihon or Trimorphodon, would likely be 

 followed by marked local symptoms. 



The poison of the Opisthoglyph snakes appears to exert a 

 powerful, benumbing influence upon the prey, which, when 



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