BRAIX AND SPINAL CORD OF RAT. 



240 

 220 

 200 

 180 

 160 

 140 

 120 

 100 

 80 

 60 

 40 

 20 



Gms. 



20 



60 



200 



80 100 120 140 160 180 



To show in the ablno rat, the body length in millimeters according to body weight in grams. Records for 170 males «, and 148 females X. The theoretic curve for the 



is based on formula (4). 

 iHE JonnNAi, or Compaeative Nedeolooy and Pstcholoqi. — Vol. XIX, No. 2. 



300 320 



sexes combined 



