Smithsonian Report, 1894. 



Plate XLVl. 



Tde 2ventr 



<'\^;i!'l.i^tuUwKiiHmiM 



Fig. 1. — Simultaiif^ous tracing-.s showing tlio pressure of the blood and 

 the arterial pulsations under the action of (h'g:itahne. 



Fig. 2.— Tracing showing tlie diminution in the vohune of a fiuger in 

 consequence of the contraction of its vessels. 



