SIGNIFICANCE OF PULSE RATE BUCHANAN. 505 



if the action of the vagus on the heart were prevented, e. g., by the 

 administration of atropine; whether in such case the frequency of 

 beat was reduced to the same extent, and if so, secondly, whether 

 under a continuation of the treatment heart acceleration occurred, 

 and occurred as promptly, on awakening from hibernation. If in 

 spite of such procedure the a'nimal when awake still succeeded in 

 regulating its temperature, we should know that other agencies than 

 the central nervous system were more intimately concerned in adapt- 

 ing the heart to meet the demands made upon it. We should then 

 be in a better position than we are now to discuss whether the power 

 which we have shown to be exercised by the heart in the different 

 species of warm-blooded animals of complying with the demands 

 made upon it, not on occasion only but for life, has been evolved 

 under nervous control. 



BEFERENCES. 



(1) Kolff, Arch. f. d. ges. Physiol. (Pfluger), Vol. 122, 1908. 



(2) Bryan-Robinson, 1734 : quoted by (2a) Mulleu, Die Massenverhaltnisse des 



menschlichen Herzens, Hamburg and Leipzig, 1882 ; and by Hoesslin, Arch, 

 f. (Anat. u.), Physiol., 1888. 



(3) Parrot, Uber die GrOssenverhiiltnisse des Herzens bei VOgeln, Zool. Jahrb., Vol. 7, 



Syst., 1894. 



(4) Buchanan, On the Frequency of the Heart-beat in the Mouse, Proc. Physiol. Soc, 



November, 1908. Journal of Physiology, Vol. 37. 



(5) , On the Frequency of the Heart-beat, etc., in Birds, Proc. Physiol. Soc, 



March, 1909. Journal of Physiology, Vol. 38. 



(G) , On the Electro-cardiogram, Frequency of Heart-beat, etc., in Reptiles, Troc. 



Physiol. Soc, December, 1909. Journal of Physiology, Vol. 39. 

 (6a) , The frequency of the Heart-beat in the Sleeping and Waking Dormouse, 



Proc. Physiol. Soc, June 18, 1910. Journal of Physiology, Vol. 40. 



(7) , Results of hitherto unpublished observations and experiments made in 



Oxford with the aid of grants from the Government Grant Committee of the 

 Royal Society. 



(8) Bergmann, Ueber die Grosse des Herzens bei Menschen und Thieren, Inaug. Dissert. 



Miinchen, 1884. 



(9) Joseph, The Ratio between Heart-weight and Body-weight in various Animals, 



(Journ. Exp. Med., Vol. 10, No. 4, 1908. 



(10) Martin, C. J., Thermal adjustment and respiratory exchange in Monotremes and 



Marsupials, Phil. Trans. B., Vol. 195, 1902. 



(11) Hering, Ueber d. Beziehung d. extracardialen Herznerven zur Steigerung d. 



Herzschlagzahl bei Muskelthiitigkeit, Arch. f. d. ges. Physiol. (Pfluger), Vol. 60, 

 1895. 



(12) MacWilliam, On the Influence of the Central Nervous System on Cardiac Rhythm, 



etc, Proc. Royal. Soc, Vol. 53, 1893. 



(13) Franck, Anatomie der Hausthiere. 

 (13a) Forbes, Proc Zool. Soc, 1881, p. 960. 



(14) Haldane, Journal of Physiology, Vol. 18, 1895; Trans, of the Institution of 



Mining Engineers, vol. 38, 1910, and other papers there referred to. 



(15) Bowen, A Study of the Pulse-rate in Man, as modified by muscular work. Con- 



tributions to medical research, dedicated to Victor Clarence Vaughan, Mich- 

 igan, 1903. 



(16) Pembrey and Hale White, Regulation of Temperature in Hibernating Animals, 



Journ. Physiol., Vol. 19, 1896; or (16a) Pembrey's article on Animal Heat in 

 Schafer's Text-book of Physiology, 1898. 



(17) Pembrey, Respiration and Temperature of the Marmot, Journ. Physiol., Vol. 17, 



1901. 



