

BRAINS AND BRAIN PRESERV A.TIVES. 



By Ales Hrdlicka, 



Assistant Curator, Division of Physical Anthropology. 



PART I. 



PHYSICAL CHANGES IN HUMAN AND OTHER BRAINS COLLECTED 

 UNDER DIFFERENT CONDITIONS AND PRESERVED IN VARIOUS 

 FORMALIN PREPARATIONS. 



Anatomical and anthropological investigations on the brain to 

 determine the homologies and differences in the organ and all its parts, 

 between man and other animals, and between races and other groups 

 of mankind, make large collections of brains necessary. Such collec- 

 tions imply the use of means b}^ which the brains can be kept indeli- 

 nitel}' in good condition for study. An ideal means would be. one 

 which would allow" every specimen to preserve its form, size, weight, 

 and all macroscopical as well as minute features. The need for such 

 an agent has long been felt and led from dry preparations to the use 

 of various liquid preserv^atives, among which, subsequently to the 

 introduction of that chemical in 1S9I: by Blum, have been solutions 

 containing formaldehyde. 



The commercial solutions of formaldehyde, known ordinarily as 

 formol, or formalin, have, even when much diluted, the qualitv" of 

 rapidly penetrating and hardening brain tissue, allowing but little 

 alteration in the form of the organ and preserving much of its color. 

 Furthermore, when hardened, specimens can be kept in the formalin 

 solution without further noticeable change quite indefinitely and the 

 preservative is not expensive. The chemical, however, is not wholl}" 

 without objections; some persons are affected adversely by its fumes, 

 the volume and weight of the brain are increased somewhat in its 

 solutions, and it does not serve best the purposes of histology; yet the 

 other advantages of formalin are so great that, until something more 

 efficient be discovered, it can not well be dispensed with for brain 



preservation. 



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Proceedings U. S. National Museum, Vol. XXX— No 1451. 



245 



