SERPENTS. 



447 



3. Ophidia. 



IN the class of serpents we see exemplified the 

 greatest possible state of simplicity to which a 

 vertebrated skeleton can be reduced ; for, as may 

 be seen in Fig. 201, which shows the skeleton 



201 



of a viper, it consists merely of a lengthened 

 spinal column, with a head but little developed, 

 and a series of ribs ; but apparently destitute of 

 limbs, and of the bones which usually connect 

 those limbs with the trunk ; there being neither 

 sternum, nor scapula, nor pelvis.* In the con- 



* Professor Mayer has, however, traced obscure rudiments of 

 pelvic bones in the Anguis fragilis, the Anguis ventralis, and 

 the Typhlops crocotatus, and is of opinion that they exist 

 much more generally in this order of reptiles, than has been 

 commonly imagined. Some serpents, as the Boa, Python, Tor- 

 tryx and Eryx, have claws, which may be considered as rudi- 

 ments of feet, visible externally. In others, as the Anguis, Typh- 

 lops, and Amphisbcena, they exist concealed under the skin. 



