58 COLUBERS. VENOMOUS SERPENTS. 



56. The COLUBERS PROPERLY so CALLED, Coluber, have the 

 head covered by large plates, (Fig. 19.) and neither fossettes on 



Fig. 19. tne sides of the muzzle, nor hooks near the 



anus. The number of these Serpents is 

 immense; the most common in France, 

 (frig. 19.) is the Ringed Snake, Coluber 

 natrix, it is ash-coloured with black spots 

 along the flanks, and three whitish spots 

 form a collar around the neck. Its length 

 is about three feet ; it is found in the neigh- 

 bourhood of stagnant waters. It swims 

 with ease, and lives chiefly on insects, mol- 

 lusks, and frogs ; it does not attempt to bite, 

 COLUBER. except when very much irritated, and the 



wound it inflicts is by no means dangerous. It is eaten in many 



French provinces. / 



57. VENOMOUS SERPENTS are provided with a particular gland, 

 situate on each side of the head, which pours out the poison that 

 it secretes, by an excretory duct, the extremity of which empties 



into one of the maxillary teeth 

 of the upper jaw. This gland, 

 (Fig. 20, g.) is placed beneath 

 the temporal muscles, so as to be 

 compressed when they contract, 

 and this tooth which is larger 

 than the others, is sometimes per- 

 forated by a canal, and at others, 

 simply has a gutter on one side ; 



RATTLE SNAKE. but in either case, its duct is in 



communication with the excretory canal of the venomous gland, 

 and serves to pour the poison into the bottom of the Wound made 

 by the tooth itself. This liquid is a most violent poison. It is 

 neither acrid nor burning, and only produces a sensation on the 

 tongue analogous to that occasioned by a fatty matter, and may 

 be swallowed with impunity ; but, introduced into a wound, in 

 sufficient quantity, it causes death with frightful rapidity. 



* Explanation of Fig. 20. Poison apparatus of a Rattlesnake : g. the 

 venomous gland, the excretory canal of which empties into a large moveable 

 tooth, (c,) m. the elevator muscles of the jaw which partly cover the gland 

 and compress it, s. salivary glands along the edge of the jaws, n. the 

 nostrils, beneath which is seen the fossette, or pit, which distinguishes these 

 serpents and trigonocephali from the vipers. 



56. What are the characters of Colubers properly so called ? What are 

 the characters of the Ringed Snake ? What are its habits ? 



57. What peculiar apparatus distinguishes the venomous Serpents ? What 

 are the properties of their venom ? 



