Page:Natural History, Reptiles.djvu/153

From Wikisource
Jump to navigation Jump to search
This page has been validated.
SERPENTS.
145

Perhaps this last feature depends on the flattened form of the head, the glare of the eye, (which is not furnished with eyelids, and frequently has the pupil linear), and the extreme width of the gape.

HEAD OF BOA.

In the Serpents, the four limbs which we have seen gradually to become obsolete in the latest forms of the Saurian group, are no longer found, either in external projections or in internal bones; there is neither breast-bone, nor pelvis, nor shoulder. In one Family, however, there are two horny spurs or hooks on the hinder part of the body, which are connected with minute bones imbedded in the flesh, and seem to be the rudimentary representatives of posterior limbs; they are, however, of no use in progression, but answer