Also, that the places to be considered were desert, so far as human habitation or population are considered.

In the vast desolation of such a place as complied with the necessary conditions, there must have been such profusion of natural growth as would bar the progress of men formed as we are.

The lair of such a monster would not have been disturbed for hundreds--or thousands--of years.

Moreover, these creatures must have occupied places quite inaccessible to man.

A snake who could make himself comfortable in a quagmire, a hundred feet deep, would be protected on the outskirts by such stupendous morasses as now no longer exist, or which, if they exist anywhere at all, can be on very few places on the earth's surface.