PARTIAL DICLINISM. 223 



protandrous ; (2) that variation in size of the flowers has 

 always taken place, not among the flowers on a single plant, 

 but between the flowers on different individuals.'' 



Mr. Darwin suggests another view : * " As the production 

 of a large supply of seeds evidently is of high importance 

 to many plants, and . . . the females produce many more 

 seeds than the hermaphrodites, increased fertility seems to 

 me the more probable cause of the formation and separation 

 of the two forms." 



" S. M.," reviewing Mr. Darwin's work in the Journal of 

 Botany, 1877, p. 375, "felt compelled to differ from the 

 author, and adds, " For ourselves we cannot help thinking 

 that gynodioBcism can be better explained on the view of a 

 sufficiency of pollen for the fertilisation of all the individuals 

 of a species being produced by only a few of the flowers, 

 so that instead of some of the anthers of all the flowers 

 becoming abortive — a very common occurrence — we see here 

 abortion of all the anthers of some of the flowers. . . . All 

 known instances of gynodioecism relate to species which 

 have the maximum of stamens possessed by the orders to 

 which they relatively belong, and are without any complex 

 entoraophilous structure. ', . . We may also remark on the 

 pauciovulate condition of gynodioecious species, and ask why 

 do we not see this form of sexual separation in multiovulate 

 ones ? " 



In reply to this writer's suggestions, I would remark 

 that ia all entoraophilous flowers far too much pollen is 

 produced and wasted ; that Mr. Darwin's observation, that 

 a bee could fertilise ten pistils with pollen from one flower 

 of Satureia, might readily apply to hundreds of cases where 

 no gynodioecism exists ; and as long as insects visit flowers 

 the tendency is not to contabescence and abortion of the 

 * Forms of Flowers, p. 304. 



