60 THE HISTOEY OF ANIMALS. [B. III. 



spines in the flesh separated from each other. Serpents are 

 like fish, for their back-bone is spinous ; among oviparous 

 quadrupeds the greater animals have a bony vertebral 

 column ; the lesser have a spinous one. 



8. Tor all sanguineous animals have either a bony, or a 

 spinous column. The remainder of the bones exist in some 

 animals, but not in others, for if they have the limbs, they 

 have the bones belonging to them ; for those that have not 

 hind and fore legs have not hams, nor are they present 

 in those animals which possess limbs unlike those of quad- 

 rupeds, for in these they vary in size and proportion. This 

 is the nature of the bones of animals. 



CHAPTEE VIII. 



1. CAETILAGE is of the same nature as bone, but it differs 

 in the greater and less, and neither bone nor cartilage are 

 reproduced if they are cut off. In sanguineous and vivi- 

 parous animals living on the land the cartilage is imper- 

 forate, and does not contain marrow, like the bones ; but the 

 flat selachea, which have a cartilaginous spine, have a carti- 

 lage analogous to bone containing a liquid marrow. Vivi- 

 parous animals, with feet, have cartilage about their ears, 

 nostrils, and extremities of their bones. 



CHAPTEE IX. 



1. THEEE is another class of parts, which, though not the 

 same as these, are not very different, as nails, hoofs, claws, 

 and horns, and besides these, the beak of birds which alone 

 possess this part. For these are both flexible and fissile. 

 But bone is neither flexible nor fissile, but brittle ; and 

 the colour of horns, nails, claws, and hoofs follow the 

 colour of the skin and the hair : for in black animals the 

 horns are black, and so are the claws and hoofs in those 

 with claws ; in white animals they are white. There are 

 also intermediate colours, the nails also are of the same 

 nature. 



2. But the teeth are like bones ; wherefore, in black men, 

 Ethiopians, and such like, the teeth and the bones are 

 white, but the nails are black, like the rest of the skin. 



