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THE ROYAL SOCIETY OF CANADA 



3. The percentage of glycogen in the heart is much higher in dogs 

 than in rabbits, both diiri?ig starvatioyi and after feeding. Thus, the 

 average of all the determinations for the whole heart in fed dogs is 

 0.540 per cent, and in starved dogs 0.739 per cent.; in fed rabbits 

 the average is 0.108 and in starved rabbits, 0. 177 per cent. 



4. In the rabbit the percentage of glycogen in the heart is always 

 less than that in the skeletal' muscles whereas in the dog the heart {ve7itricle) 

 contains a higher percentage than the skeletal muscles in starved animals 

 but a decidedly lower percentage in those that are fed. These facts are 

 best brought to light by comparison, not of averages but of determina- 

 tions made on the two tissues in individual animals. The following 

 figures will serve to illustrate these relationships: 



(Per cent. Glycogen) 



Animal 

 Rabbit 2a. 



Rabbit 3a. 



Rabbit 2.. 



Rabbit 3 . . 



Dog 5.. 

 Dog 6.. 

 Dog 7.. 

 Dog 8.. 

 Dog 9.. 

 Dog 10. 



Bibliography 



1. Pfluger, E. F. W. — Archiv fur die Gesammte Physiologie, 1903, 



xcvi, 1. 

 Lewis, T.- — The Mechanism and Graphic Registration of the Heart 

 Beat. London, 1920, P. 11, 93. 



2. Cruickshank, E. W. H.- — ^Journ. of Physiology, 1913, xlvii, 1. 



3. Kilburn, L. G. and Macleod, J. J. R.— Quart. Jour. Exp. Physiol., 



1920, xii, p. 317. 



