GEOLOGY. 69 



dry before these wells were bored. The artesian wells cannot 

 draw the water from the soil immediately around them, for 

 they throw their waters above the earth ; it may be, however, 

 that their supplies are derived from the soil in the upper part 

 of the valley — supplies which, if the wells were not there, 

 would not be drained away into subterranean channels, but 

 would go to moisteif the whole valley. It is to be observed 

 that, at the very time when the soil of the Santa Clara valley 

 was becoming so dry, a similar disappearance of the surface- 

 water was noticed far beyond the influence of the artesian wells 

 — Honey Lake, on the plateau of the Sierra Nevada, and Lake 

 Elizabeth, in the Great Basin, both disappearing about the 

 same time, in 1859; and several other little lakes and ponds 

 in other parts of the country following their example, soon 

 after. 



There are artesian wells at various places in the state besides 

 Santa Clara valley, but they offer nothing new in a geological 

 point of view, 



§ 48. Paleontology. — It is a general rule, that the animals 

 of former geological eras, in any given district, appear to have 

 been the gigantic ancestors of those of the present time. Thus 

 the kangaroo and emu of Australia, found in no other part of 

 tlie world, were preceded by gigantic kangaroos and emus, 

 whose fossil remains are found in New Holland only. So, too, 

 South America, in antediluvian times, had gigantic sloths and 

 tapirs, akin to the animals now found within her limits. Each 

 continent has a fauna of its own, to which its antediluvian ani- 

 mals were nearly akin. Every continent has several zoological 

 districts ; and the ancient and modern fauna of these districts 

 are sometimes as clearly related to each other, and as distinctly 

 separate from those of other parts of the continent, as arc the 

 fauna of different continents from each other. But the ante- 

 diluvian animals of California possessed no peculiar relation- 

 ship to the animals now indigenous in the state : the former 

 fauna was totally distinct from that of the present age ; the 

 fossil bones found are not numerous, and no large and valuable 



