1^8 'Journal of Comparative Neurology and Psychology. 



females (see Chart II, based on 179 males and 160 females) it 

 will be observed that the latter rnn slightly below the former. The 

 difference, thongh small, has significance, as we shall show later. 

 However, for the general discnssion at this time the resnlts are 

 not separated according to sex, but are treated together. 



TABLE 1. 



The Ratios Obtained by Dividing the Body Length by the Weight in 



THE Case of Mus Norvegicus Var. Albus. 



The theoretical curve which most closely represents the change 

 in body length with increasing body weight, is given by the 

 formula (4) 



y = 143 log (x + 15) — 134 



where y represents the body length and x the body weight. 



This is a formula of the same type as those used for determining 

 the weight of the brain and of the spinal cord in relation to the 



