350 The American Geologist. May, lau 
sketch of thoir possible ancestors — glacial man — and in this part of the 
volume geologists will have the more lively interest. 
While the author has not been among the credulous in accepting the 
supposed tokens of paleolithic man in America, he yet gives approv- 
ingly the points of coincidence between the European and American 
discoveries, and he so unites them in his presentation that it is evident 
that he recognizes a "paleolithic" human age in America. He quotes 
Dr. Abbott's discoveries in the Trenton gravels and Miss Babbitt's opin- 
ions of the quartzes at Little Falls. He figures the Nampa image, 
quotes Prof. Whitney on the Calaveras skull, and Dr. Flint on the 
"Eocene or Miocene" human footprints in volcanic tufa in Nicaragua. 
He considers that Dr. Koch's claims as to the association of human im- 
plements with the mastodon (the Missourium of Dr. Koch) have been 
confirmed by the recent discoveries of Dr. Hughey (Aughey?) in Ne- 
braska and by his own in Ohio. In all these cases the bones of the mas- 
todon are mixed with ashes and other traces of fire, arrow-heads and 
other stone weapons. He also adopts the Davenport elephant pipe, about 
which there has been much discussion. He classes these among the 
"mysterious races," of whose origin and whose dates we have nothing 
certain, further than that they were contemporary or immediately suc- 
ceeding to the glacial epoch. It would be well here to note an error in 
the illustration intended to show the vicinity of the "Second find," i. e. 
Little Falls, Minnesota (page 4). The figure instead is a reproduction 
of a sketch map of the region of St. Anthony falls, which are about 100 
miles south of Little Falls. Aside from the doubtfulness of other evi- 
dences of paleolithic man in the United States, recently subjected to 
close scrutiny by Mr. W. H. Holmes, Mr. J. Crawford has shown (Am. 
Geologist, Vol. X, p. 100) that the human footprints in the volcanic 
tufa of Nicaragua are probably of even historic date, and that Dr. Earl 
Flint's observations were quite incorrect. 
Of the Mound Builders the author has made a long and thorough 
study. He comes at first to the conclusion that they were not the an- 
cestors of the modern Indians, or if they were that their works are so 
distinctive that they should be entirely separated from them in such an 
investigation. Where the remains of both are found in the same region 
they can be distinguished. 
As to the Mound Builders proper they are divided by the author into 
several classes, and into different epochs distinguishable by varying 
structures, these being the result of natural adaptation to physical sur- 
roundings, rather than of age, or stage of progress. The peculiarities 
which distinguish the works of the true Mound Builders from the works 
of more recent inhabitants of the region, "arise from their being exclu- 
sively earthworks, and, first, their solidity; second, their massiveness; 
and third, their peculiar forms." The author makes eight geographical 
divisions of the Mound Builders, and points out severally their char- 
acters. In this, however, he evidently blends the Mound Builders with 
the historic Indians, assigning to them the same peculiarities and struc- 
tures as mark the Indians that are known to have occupied the same 
