SPECIES IDENTITY OF NUCLEUS-PLASMA NORM 453 



jective anatomical diagnosis of the absence of frank functional depression 

 after a single large and symptom-producing dose. Such variations 

 as were found went with the obvious degree of senility of the cells 

 measured (table 5). 



Experiment Normal 18 (table 5). A muscular and well nourished 

 female, of predominant bull strain. It had given birth to pups three 

 weeks prior. This animal, presumed to be a normal, exhibited frank 

 anatomical depression and was used for measurements of cells in that 

 state. 



TECHNICAL METHODS 



Only an outline necessary to clear understanding is inserted 

 here. The factors which might lead to error are most appro- 

 priately summarized under "Technical factors in their relation 

 to the results," because their relative importance will be plainer 

 after the essential results are stated. Further, as the tedious 

 data in this section to follow are only contributory to the main 

 theme, that section may be omitted unless the possible interest 

 is in criticism or repetition. 



I desire to express my thanks to my colleagues in Mathematics, 

 Prof. E. R. Hedrick and Prof. O. D. Kellogg, for their painstaking 

 elucidation at many times of various mathematical principles 

 involved. However, they are not to be held responsible for 

 my possibly anomalous manner of discussion of an unfamiliar 

 subject. 



I . The calculation for aggregate cells from the average of 

 measurernents 



The technic of measurement and the principles of calculation 

 have been previously discussed in sufficient detail ('10, '13 a). 

 Each set in tables 1 and 5 represents the average of twenty- 

 five resting cells. It is very seldom that this number has not 

 been found amply sufficient to give a fair average among the 

 different stages of activity. Ten cells give a constant relation 

 more frequently than they do not. The measurements were 

 made on camera lucida projections. The longitudinal and 

 transverse diameters of both cells and nuclei were ascertained in 

 terms of the half-millimeter as a unit, an average was taken, and 

 the figures reduced to micra. The long diameters multiplied by 



