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THE SCIENTIFIC MONTHLY 



viduals of different body weights, represent these averages by a 

 series of points and smooth them with a straight line. Thus 

 Fig. 4 shows quite clearly that the daily heat production of indi 

 viduals tends to increase in a sensibly linear manner with their 

 mass. 



For exact comparison we must have recourse to some pre 

 cise method of expressing the degree of relationship between 

 physical characters and basal metabolism. This may be done 

 by the use of the coefficient of correlation which measures the 

 degree of interdependence of two variables on a universally 



BODY S/EIGHT IN KILOGRAM.S 



FIG. 4. RELATIONSHIP BETWEEN BODY WEIGHT AND DAILY HEAT PRODUCTION. 

 Actual averages and fitted straight lines. 



comparable scale of unity. We find the values for the correla 

 tions between stature, body weight and body surface on the one 

 hand, and total daily heat production on the other given in the 

 accompanying table. 



The coefficients measuring the relationship between body 

 weight and metabolism are in all cases higher than those be 

 tween stature and metabolism. Body mass is, therefore, a more 

 important factor in determining (in the proximate but not 



