90 POISONOUS SNAKES ATSTD SNAKE POISONS. 



and entering into one another ; and thus the vertebral 

 column is very strong, while at the same time it has 

 great freedom of motion. It must be added, however, 

 that, in accordance with this structure, there is little or 

 no niatural upward and downward undulation of the 

 body as the apophyses prevent that ; all the undulations 

 are from side to side. Nearly each of the vertebrae has 

 a pair of ribs which serve not only to give the body its 

 form, but help in breathing and in locomotion. 



Also the ribs are extremely movable ; their free ends, 

 in fact, being simply attached by muscular fibres to the 

 scales or " scutes," which cover the lower or abdominal 

 surface of the animal, so that they can easily be drawn 

 backward and forward. By means of this arrangement, 

 snakes are able to progress rapidly, walking, as it were, 

 upon the ends of the ribs, just as other animals get along 

 on their feet. 



It is impossible for them, however, to jump great dis- 

 tances, nor are they able to erect more than the first 

 third of their body ; so that all reports telling us about the 

 terrible speed which snakes attained while pursuing 

 other animals or human beings, as well as accounts of 

 enormous heights which snakes jumped in order to reach 

 their victims, may safely be rejected as fairy tales. We 

 know positively that no snake can run so swiftly that a 

 man could not, without running, walk along side of it 

 with long steps, but we may account for the frequent ex- 

 aggerations by the circumstance that the winding, 

 wriggling motion of a snake offers a rather unsteady pic- 

 ture to the human eye, and as, moreover, very few people 

 really take pains to observe the speed of snakes care- 

 fully, everybody is convinced that it must be very great. 

 The same reason may be given when we hear from other- 

 wise quite reliable persons that ihey saw snakes jumping 

 to an utterly imposible height. Most snakes are scarcely 

 able to raise their heads more than one or two feet above 



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