DoNALDSON-ScHOEM AKER, Newous Systetu of Frogs. 117 

 V. Chart I. 



Chart I, shows by the solid lines the weight in milligrams 

 of the Brain and Spinal Cord in Bull-frogs up to 146.9 grms. 

 of body-weight. Compared with these are the records for R. 

 virescens brachycephala. For this latter species the weight of 

 the brain is indicated in each case by a black circle • for the 

 males, and a ring o for the females. The weight of the cord 



