10 



Macfarlane. — Contributions to the History of 



Another leaf was acted on as follows : 



ist stimulus no effect. 



after sixty seconds, " 



2d 



3d 



4th 



5 th 



6th 



7 th 



8th 



9th 



fifty 



scarcely perceptible closure, 

 little if any closure, 

 no effect. 



ioth 



decided though slight closure. 



leaf now closed fully one- 

 third and movement pro- 

 longed through twenty-five 

 seconds. 



leaf closed after movement 

 of sixteen seconds. 



A rather small leaf was then acted on as follows : 

 ist stimulus no effect. 



extremely slight closure, 

 no visible closure. 



very slight closure. 



leaf fully half closed after 

 movement of fourteen sec- 

 onds. 



leaf closed after movement 

 of thirteen seconds. 



A medium-sized healthy leaf was acted on thus : 



ist stimulus no effect. 



2d " after forty-five seconds " 



3d " " forty " " 



4th " " thirty-five " extremely slight closure. 



5th " " thirty " about half closed. 



6th " " twenty-five " entirely closed. 



Another of similar size as the last behaved as follows : 



ist stimulus no effect. 



i oth 



2d 



3d 

 4th 

 5 th 

 6th 

 7 th 



after sixty seconds, 



(I 



(( 



fifty 





very slight closure, 

 leaf half closed. 

 " closed. 



