46 SNAKES. 



blooded. Cuvier divided the egg-producing animals into 

 oviparous quadrupeds (lizards, turtles, crocodiles, and frogs) ; 

 bipeds, the birds ; Insects and serpents. Linnaeus — who, by 

 the way, preceded Cuvier — called all reptiles ' amphibious 

 animals/ of which serpents were the second order, those 

 * without limbs.' He also divided them into orders, genera, 

 and species ; but in the Ophidia was guided too much by 

 the scales, which has caused confusion ever since, as both 

 poisonous and harmless snakes often present similar cha- 

 racters in this respect. 



If the reader will turn to the illustration of scales (p. 193), 

 he will see an example of the large scutae or ventral plates 

 that are possessed by the majority of the true Ophidia. 

 The burrowing snakes, most of them small and allied to 

 lizards in their structure, are protected by a cuirass of hard, 

 close-set, polished scales, alike all round ; or else with a 

 thick, smooth skin arranged in rings. Some very poisonous 

 serpents, notably the sea-snakes, have also the scales alike 

 all round, because they do not require the hold which those 

 large ventral scales afford to land serpents in progression ; 

 but it will at once be seen that on so slight a 

 resemblance It would be unsuitable to arrange 

 such widely-differing families in the same group. 

 The majority of snakes have the scales under 

 the tail different from those under the body ; 

 and a very large number, both of venomous 

 and innocuous snakes, have broad ventral scales, 

 as far as the termination of the body, and then 

 a double row where the tail commences. The 

 accompanying illustration is sufficient to convey 



