BY ALEX. G. HAMILTON. 17 



Having completed my theory, I took the first opportunity of 

 putting it to the test by visiting a flowering plant in the dusk, 

 and I then found that tlie method was exactly as above set forth. 

 Numbers of hawk moths of the species Deilephila celerio were 

 very busy extracting tlie nectar, and as they balanced on the wing 

 above the flowers, invariably touched the anthers of those in the 

 first stage ; or the stigma in those which had reached the second, 

 both with their legs and their bodies. As might be expected the 

 plant fruits freely but not invariably. 



I have little doubt but that the flowers may also be visited and 

 fertilised by the little Cobbler's Awl, Acanthorhynchua tenuirostris-, 

 which is very fond of visiting tubular flowers, but so far I have 

 not observed them at it. Crowds of small moths were fluttering 

 about the flowers, probably attracted by the sweet scent, but thev 

 did not alight : perhaps the d^^pth of the tube and the want of a 

 platform for resting on deterred them. 



After writing the preceding, I came across the following, which 

 has a good deal of interest as bearing on fertilisation in this 

 manner. "Natural Science" (Vol. iii. p. 415) notices a paper by 

 Di-. Max Schnltz in Cohn's Beitiage zur Biologie der Pflanzen 

 (Vol. vi. p. 305) " On the movements of the stalk and flower, of 

 Cobcea scandens." 



The flowers are proterandrous and the two upper stamens shed 

 pollen first, the anthers standing up before the entrance to the 

 flower, and then bend downwards out of the way. Then the three 

 lower anthers take up the same position and open, afterwards 

 bending downwards, while the style takes the position formerly 

 held by the anthers, and the stigmas unfold. 



After reading this, I v/atched a plant of Cobcea in flower, and 

 was struck with the similarity of the process to that in Cleroden- 

 dron. Although Dr. Schultz (as quoted) says that two anthers 

 open first and then the other three, I noted that in ray plant the 

 anthers frequently opened singly, or irregularly as in Clerodendron, 

 or all at once. 



The notice concludes with the following words : — "These move- 

 ments of the flower and its stalk are, perhaps, a device for ensuring 

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