332 ON THE FRUITING OF WISTARIA SINENSIS. 



tliis case of all the flower-structures) are seen to be blackened and 

 dead, while every thing else is apparently uninjured. I am not pre- 

 pared to say that this is what happens in the case of Wistaria, 

 though it is well known that its flowers are peculiarly apt to re- 

 ceive injury from spring frosts*; but I believe I am justified in 

 concluding that the low night-temperatures of early spring are the 

 probable cause of the sterility of our cultivated Wistaria, whether 

 due to failure of fertilization or subsequent non-development of 



the fertilized ovaries. 



There is the further question whether, as suggested by Mr. 

 Meehan, the mode of growth in the cultivated Wistaria could 

 have anything to do with its supposed uniform sterility. The 

 view that it does so appears to me to rest on a mistaken applica- 

 tion of a general principle — the antagonism of vegetative and re- 

 productive activity. When a plant, from the mode of its culti- 

 vation, fails (as too often happens in our horticultural experience) 

 to produce flowers, and develops in their place leafy shoots, we 

 are justified in describing this as a diversion of the nutritive re- 

 sources of the plant from sexual reproduction to vegetative growth. 

 The generalization is, I believe, often carried too far, inasmuch as 

 the reproductive function is characteristic of the adult stage of 

 the organism ; and it is for this reason that so many arboreal 

 plants are barren when young, just as with animals, in whom the 

 sexual characters are the crown and completion of the whole pro- 

 cess of organic evolution. 



But in the Wistaria I fail to see any evidence of such an anta- 

 gonism, any more than in the Scarlet Eunner. In fact, if it ex- 

 isted, it would not so much suppress fruit as suppress the flowers ; 

 and it is a matter of ordinary experience that in the Wistaria 

 these are produced in remarkable profusion. But, in fact, there 

 is nothing remarkable in the mode in which the Wistaria is ordi- 

 narily grown. It is a scandent shrub ; and its attachment to a 

 wall or trellis merely takes the place of the adventitious aids 

 which it would obtain in a feral state. If the scandent habit 

 (for this is all its trained condition amounts to) were the cause of 

 its barrenness, it, and a host of other plants with a similar habit, 

 must ages ago have become extinct. 



In 1872 the blooms in English gardens were killed by the frosts of March 

 23 and 24 (Journal of Horticulture, vol. xlvii. p. 442). 



