TEE LOESS. 411 



Professor Hilgard explains that the terrestrial fossils are, as 

 a matter of fact, found near the marginal portion of the loess, 

 where the destructive processes are least. Whether, also, 

 there may not be a difference between the destruetibility of 

 land- and fresh-water shells is also a question. The occur- 

 rence of nodules of lime throughout the mass points to such 

 a work of solution and redistribution by water. In regard to 

 the frequent occurrence of the bones of the larger land-ani- 

 mals, Professor Hilgard remarks : " That the phosphatic 

 bones should not have dissolved as easily as the mere carbon- 

 ate shells is readily intelligible ; and as regards their mode of 

 occurrence in the loess of the lower Mississippi they are 



Fig. 119.— Stratification of the loess in a railway cut at Plattsmouth. Nebraska, at a depth 

 of eighty-four feet from the surface. (From photograph furnished by Dr. A. L. 

 Child, of Kansas City. Mo.) (Chamberlin.) (United States Geological Survey.) 



always very much scattered, many bones belonging to the 

 same individual being rarely found together, but seeming to 

 have drifted widely apart. It is not easy to see how the 

 cumbrous bones of the mammoth could have been widely 

 separated in a subaerial deposit." * 



* "American Journal of Science," vol. cxviii, 1879, p. 110. 



