6 OSBORN, Staminal Mechanism of Passiflora Caerulea. 



know what meaning to attach to the words " directed 

 outwards." Moreover, it is certainly this movement of 

 the stamen as a whole that brings the " pollen-covered 

 lobes of the anther towards the interior of the flower." 

 I am bound, however, to state that I have not had the 

 opportunity of reading Warnstorfs paper, and have been 

 obliged to interpret his meaning as well as I can from 

 the reference in Knuth. 



After this second stage the flower closes, and Knuth 

 suggests the possibility of autogamy at this period, since 

 the stigmas and anthers may be brought into contact in 

 the closed flower. I am inclined to think that this must 

 be rare, having examined a considerable number of 

 closed flowers, I have found the styles between the ring 

 of outer rays and the petals, the stamens inside the 

 coronae, and no pollen on the stigmas. 



Summary. 



The staminal movements to which I wish to draw 

 attention and to place in the order of their sequence 

 are : — 



a. A radial movement of the anthers on the filament 

 of 1 80°, which occurs as soon as the flower opens. 



j3- A second movement of the anther through 90° 

 into a plane at right angles to the first, i.e., into 

 the tangential plane, in which position a special 

 mechanism is called into play to retain it there. 



7. The radial movement in two stages of the stamen 

 as a whole, so as to bring it from an erect to a 

 drooping position ; the first stage of this move- 

 ment being, in part, concurrent with j3, and 

 coextensive with the first stas^e of anthesis. 



