The Journal of 



Comparative Neurology and Psychology 



Volume XIX May, 1909 Number 2 



Ol!^ THE RELATIO:^ OF THE BODY LENGTH TO THE 



BODY WEIGHT AND TO THE WEIGHT OF THE 



BRAIN AND OF THE SPINAL CORD IN THE 



ALBINO RAT (MIIS NORVEGICUS 



VAR. ALBUS). 



HENRY H. DONALDSON. 



Profcsfior of Nci(rolof/ij at The Wi!<f<ir Institute. 



With Three Figures. 



In a recent paper (Donaldson, '08) the relations of the body 

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

 albino rat have been described. 



In addition to the determination of the body weight it was stated 

 in the paper jnst cited (pp. 340-7) that measnrements had also 

 been made on the body length (trnnk and head) of some of the rats, 

 bnt to avoid confnsion the discussion of this character and its 

 relations was reserved for the present paper. 



The reasons for making a series of linear measurements on the 

 albino rat were briefly the following: — 



1. To obtain a second general measure of the body growth of 

 the albino rat in terms other than those of weight. 



2. To gather data by which to determine the body weight and 

 body length ratio for the variety measured. 



This ratio is valuable because it gives a notion of the general 

 shape of the animal and also enables us to state whether there are 



The Journal of Comparative NErROLOGY and Psychology. — Vol. XIX. No. 2. 



