4G The American Geologist. Jan. 1891 
natural causes ? Here we call upon the mineralogists to decide 
what material will be most likely to receive accidental fractures of 
a conchoidal shape which will resemble artificial chippings. The 
quartz relics found at Little Falls, in Minnesota, have never satis- 
lied certain archaeologists ; they were not sufficiently marked in 
their artificial qualities to he selected as typical specimens. The 
argillaceous relics are not altogether satisf actor}', as there is such 
a great variety in their shapes. Many of the chert specimens 
seem so extremely rude that it is a question whether they are 
artificial or not. 
We would not, however, confine the subject to the fracture 
relics. According to some neolithic specimens of an advanced 
type are found, ante-dating, geological^ speaking, all the paleo- 
lithic specimens. Statuettes, finished in the round, such as the 
nampa image, being found beneath the lava beds, and various 
steatite ollas, or mortars, in the auriferous gravels, etc. Under 
the circumstances would it not be well for the geologists to look 
for water-worn neolithic axes and hammers, with ground edges, 
and grooves, in the loess and in the moraine gravels ? We do not 
.say that such finds are likely to occur, but since the barriers have 
given way between the two classes, we would like to cover the 
whole field, and not reject a relic which seems to belong to the 
polished stone age, even if it should appear in unnatural sur- 
roundings. It may be a thankless task, for every relic of this 
kind has been challenged. Doubts will linger for many years to 
come. The problem of man's advent upon the stage is one 
which geologists and naturalists must help to solve, for archaeolo- 
gists are inclined to admit that their science when unaided by 
other departments, will not at present furnish the tests b} r which 
we may determine the age of a relic. We are inclined to say the 
same thing also in reference to what might be called "there- 
mains, ' especially human crania. This is an unsettled, unsolved 
problem. The shape of a skull may to some minds be a proof 
of its age, but to other minds it is no criterion at all. For this, 
too. we are dependent upon the geologists to settle the question 
of age. The horizon which the geologists may recognize is the 
main test. 
