1911.] 



The Stomatograph. 



41 



are connected to the same pump. Such records might be of interest to 

 students of ecology. 



The chief interest attaches, however, to continuous field records, since 

 these are unique, excepting for microscopic examinations made by Lloyd.* 

 Eig. 4 shows the general nature of stomatal behaviour on a single adult leaf of 









_ Whole plant; screened from d/recb sun 









from /icb.m.Ju/?e 8. to 



") a.m. June 9. 



- 3 C£._per mimite 





J 







-zc.c.per minute 











- 7 cc.per minute 

 Begins at io-3oa.m. 









-yfene 8% 











Record missing till io a.m. 







\ 





J 







June io fc > 







•v. 



June ii^ 















\6a.m\ Moon \ 6p.m\ 



NIGnT ^^^^ Mrect Sunshine ^ Diffuse ZipM NIGHT 

 Sun-rise Sun, afove building Trees' shade Sunset 

 Fig. 4. 



Egyptian cotton, growing under field conditions excepting for the presence 

 of the chamber. The behaviour of Helianthus in Egypt appears to be 

 closely similar. The curve gives the number of cubic centimetres of air 

 passing through the leaf per minute in each ten-minute period. 



The circumstances under which this record was taken were roughly as follows : 

 Sun temperature with black bulb in vacuo, 65° C. Maximum shade temperature 



* Loc. cit. 



