22 ^ W. P. Wilson. 



On the '12*'^ of April the following disposal was made of the three 

 pots of I. 



The nectar was removed from all the plants in the three pots. 

 Pot No. 1 was left in the sunlight. 



April 14*^. All the nectaries excreting copiously. Nectar again re- 

 moved. 

 15*^. All the nectaries very active. 

 Pot No. 2. Placed in diffused light six meters from the, Windows. 

 April 14*^^. Of the seven pairs of nectaries from which the nectar was 

 removed only one secretes nectar to day. 

 15*^. None of the nectaries are secreting. 

 Pot. No. 3. Placed in the dark. 



April 1 4^*". Of the five pairs of nectaries from which the nectar has 

 been removed four are moist. Nectaries again dried. 

 15*^. Four pairs of nectaries dry, one pair still moist but not 

 active. 

 On April IS*'*. One pot of plants from 11. was placed in the sunlight, 

 April M^^. Two pairs of nectaries began to excrete nectar. 



15*^^. Many of the nectaries are secreting finely to-day. 

 On April 13*''. One pot from III. was placed in the sunlight. Plants 

 much etiolated; color yellow to white. 



April 14*^. Four pairs of nectaries have begun to excrete. 



15*^. Many of the nectaries are active. 

 The continuation of the excretion on a few of the nectaries placed in 

 the dark was probably an after effect of the light. 



I have placed here only a very few of the many experiments which 

 this work required. They will serve to illustrate the method employed. 



