58 Wisconsin Academy of Sciences, Arts and Letters. 



found on the other. This is not the case. The cells lie in small 

 clusters, which are seldom cut in the same position, and hence 

 the number of cells on the two sides of the same section 

 rarely corresponds exactly. It is therefore impossible to be 

 influenced by the preceding counts in such a way as to 

 " force a balance." 



I add the complete enumeration of the cells of one frog, 

 No. 43. Sections 1-146 lay in the medulla oblongata. 



