26 THE AMERICAN NATURALIST [Vol. LIV 



TABLE VII 

 Nervous System and Sense Organs 



I'.. :-.!-. .- without 



Sulfide (total). . . 

 Tuberculous mom 



150 18 Hydrocephalus. 

 60 Encephalitis... 

 70 Convulsions (nc 



tion biologically. The immediate motivation of a sui- 

 cidal death is surely internal. A searching biological 

 analysis of the phenomenon of suicide has yet to be made, 

 but certain of its biological relations are clear enough. 

 In the broadest terms people commit suicide because 

 their higher cerebral mechanism breaks down under the 

 stresses of the world in which they live, and fails to con- 

 tinue its normal functioning. One of the deepest rooted 

 instincts of the individual among all living things, from 

 lowest to highest, is the instinct for the preservation of 

 the individual life. The only instinct which transcends 

 it, and that only in comparatively few cases in lower ani- 

 mals, is the instinct of reproduction. But the phenom- 



iBln part. 



ie See footnote Table I. 



20 Less than 0.1 per 100,000. 



