GLYCOGEN IN THE NERVOUS SYSTEM OF 
VERTEBRATES 
SIMON H. GAGE 
Cornell University, Ithaca, N. Y. 
TEN FIGURES (ONE PLATE) 
HISTORICAL SUMMARY 
The brilliant series of investigations by Claude Bernard on 
sugar in the blood which culminated in his discovery and iso- 
lation of glycogen in 1857, may justly be characterized as epoch- 
making for the understanding of animal physiology, and a 
proper correlation of the physiology of animals and _ plants, 
and their fundamental similarity. 
In this series of investigations, Bernard was disturbed and 
puzzled by not finding at any period of the life of animals gly- 
cogen in the nervous system. He missed it also in other organs 
and tissues, but all the gaps were filled up by one investigator 
or another until in 1904 the glycogenic function had been dem- 
onstrated in some stage of development for all organs and 
tissues except the nervous system. 
This is what Bernard himself says (’59) and _ practically 
repeats in all of his published papers and books upon Glycogen: 
A aucune époque de l’évolution organique, je n’al pu constanter 
la matiére glycogéne dans les tissue nerveux. J’ai traité, soit par la 
coction, soit par divers autres moyens précedemment indiqués, le 
cerveau, la moelle épiniére . . . . chez des foetus d’homme, 
de veau, de mouton, de lapin, et 4 aucune age je n’ai pu y constater la 
moindre trace de matiére glycogéne. 
Barfurth (’85, p. 299) referring to what Bernard says concern- 
ing glycogen in the nervous system of vertebrate embryos, says: 
“Tech kan diese Angeben lediglich bestitigen.”’ 
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