OF PECULIAR CRANIAL FORMS. 42} 
lectionat Boston, along with other interesting illustrations of the ancient 
arts and customs of the Peruvians. This primary distinction in 
the forms of Peruvian crania, apart from the changes wrought on 
them by artificial means, must be borne in remembrance while estima- 
ting the bearings of such evidence as that adduced by Dr. Tschudi 
from the Opas Indian mummy ; for assuredly no conceivable amount 
of change in the progress from infancy to maturity, could convert the 
elongated head figured in Rivero and Tschudi’s Atlas, into the brachy- 
cephalic cranium frequently pertaining to the ancient Peruvian adult. 
But while evidence derived from various sources tends to confirm 
the opinion that at least two, if not three essentially distinct forms of 
head, prevailed among the ancient Peruvians, the evidence produced by 
Dr. Tschudi fails to prove that the examples referred to by him ought 
to be accepted as illustrations of a normal cranial type. 
In this as in so many other departments of Ethnology, the naturalist 
cannot be too frequently reminded that the most primitive condition 
of man’s savage life is an artificial one when compared with that of 
any of the lower animals. With man alone the osteologist finds his 
investigations complicated by altered forms produced by artificial means; 
and under this head must be included the accidental and undesigned, 
as well as the purposely superinduced changes effected on the human 
frame, and especially on the skull; while to causes thus operating to 
modify or counteract the normal vital functions, have to be added 
others, illustrated by the examples produced above, and clearly trace- 
able to a posthumous origin. 
The intra-uterine position of the Huichay cave foetus furnishes in- 
disputable proof that its peculiar cranial development is not due to 
art: if by this is understood the application of mechanical pressure 
with an express view to the production of such configuration ; but this 
by no means exhausts the possible sources of abnormal modification. 
It may be the undesigned result of mechanical pressure inevitable 
in the process of dessication, accompanied as it invariably was, in the 
case of Peruvian mummies, with the forcing of the body into a crouch- 
ing position, in which the legs were compressed upon the abdomen, 
and the arms folded across the chest. The naturalist who aims at 
applying the deductions of physical ethnology to the determination of 
ethnic classification, cannot content himself with accepting such osteolo- 
gical evidence as presents itself to him, in the unquestioning spirit which 
may be permissible in other branches of natural history. The most 
