988 The American Naturalist. [December, 
turtle-back. The turtle-back and the leaf-shaped implement 
are practically the same size, except the latter is only % or $ 
inches in thickness. This reduction in thickness cannot be 
done without striking the turtle-back on its edge (Plate XX VI) 
thus working its total destruction and treating it as if it were 
an original pebble. The plate will make this apparent. 
This argument demonstrates that the pretended evolutionary 
series of Mr. Holmes set forth in his Plate IV, (My Plate 
XIX) is incorrect. While all the implements are there truly 
represented, yet they do not form a continuous series. The 
leaf-shaped implements in the bottom row, “3rd stage, both 
sides re-worked,” could not be made from the “turtle backs ” 
in the two upper rows. Therefore, I deny Mr. Holmes’ funda- 
. mental proposition. I am fully persuaded that the maker of 
these implements, whatever else he intended to do, did not 
intend or attempt to make the leaf-shaped blades out of the 
turtle-back, or at least that turtle-backs were not a stage in 
the process of making leaf-shaped implements. If my proposi- 
tion in this regard be true it breaks Mr. Holmes’ theory in 
the middle. 
IV. 
Mr. Holmes Says, p. 17, “that to a limited extent, the rude 
forms—the turtle-back and its near relation—are also found 
widely scattered over the Potomac Valley outside of the shops 
on the hills.” The suggestion is that these came from this 
quarry or from similar quarries, and he charges flat-footed 
that they were the “ rejects,” “ refuse,” “ debris,” “ failures.” 
In January, 1888, the Smithsonian Institution issued a cir- 
cular, No. 36, asking of its correspondents throughout the Uni- 
ted States and Canada, for information as to the number of 
these implements in their respective localities. This was ac- 
companied with elaborate description and many illustrations, 
so there should be no mistake in theiridentity. Answers were 
then received, from every state in the United States and some 
from Canada. A consolidation of these answers, with briefs, 
was published in the Annual Report of the U. S. National 
Museum for 1888, pp. 766-702, wherein the number reported 
up to that time is stated at 8,502. This has been largely in- 
