362 Cooke and Schively on Observations on the 



have had an influence. The summer of 1899 was warm and 

 dear. In 1902 there was considerable rainfall; and August 

 and September were very cool months. 



In 1902 an attempt was made to study the comparative 

 numbers of chasmogamic and cleistogamic flowers. There 

 seems, however, to be the greatest possible variation ; some- 

 times the two are nearly equal, but often there is a marked 

 difference. The cleistogamic type predominates. The fol- 

 lowing tables present some results of these observations. 



Number of 



Number of cleistogamic Number of Number of 



axes of flowers on lower chasmogamic cleistogamic 



inflorescence, part of axis. flowers. flowers beyond. 



14 a IS 19* 3 



b 17 S I 



c II o — 



d 18 S 2 



e 19 2 2 



f 16 4 4 



g 16 7 3 



h 12 9 2 



i 13 8 2 



j 17 5 4 



k 14 6 4 



1 14 8 2 



m 10 o — 



n. 



16 o. 



208 78 29 



♦ One cleistogamic flower among these. 



