524 STIMULI APPLIED TO LEAFLETS OF SCHRANKIA 



Fig. 1. Silhouette of leaf fastened (by a quick movement) between panes of 

 glass and then fixed by heat to prevent closure of leaflets. Five pairs of pinnag 

 are shown, each consisting of about a dozen pairs of leaflets. 



Fig. 2. Silhouette made artificially to show appearance of pinna after a single 

 leaflet has been caused to close by stimulation. This result usually is seen in the 

 forenoon. 



Fig. 3. Silhouette made under artificial conditions to show appearance of pinna 

 after wave of closure has involved all leaflets distal to the leaflet originally stimu- 

 lated. This result is usually seen in the late afternoon. 



