Chap. IV.] OF INDIVIDUALS. 121 



fertilisation ; and no doubt it is useful for this end : but 

 the agency of insects is often required to cause the 

 stamens to spring forward, as Kolreuter has shown to be 

 the case with the barberry; and in this very genus, which 

 seems to have a special contrivance for self-fertilisation, 

 it is well known that, if closely-allied forms or varieties 

 are planted near each other, it is hardly possible to raise 

 pure seedlings, so largely do they naturally cross. In 

 numerous other cases, far from self-fertilisation being 

 favoured, there are special contrivances which effectually 

 prevent the stigma receiving pollen from its own flower, 

 as I could show from the works of Sprengel and others, as 

 well as from my own observations: for instance, in Lobelia 

 fulgens, there is a really beautiful and elaborate contri- 

 vance by which all the infinitely numerous pollen- 

 granules are swept out of the conjoined anthers of each 

 flower, before the stigma of that individual flower is ready 

 to receive them ; and as this flower is never visited, at 

 least in my garden, by insects, it never sets a seed, though 

 by placing pollen from one flower on the stigma of another, 

 I raise plenty of seedlings. Another species of Lobelia, 

 which is visited by bees, seeds freely in my garden. In 

 very many other cases, though there is no special me- 

 chanical contrivance to prevent the stigma receiving 

 pollen from the same flower, yet, as Sprengel, and more 

 recently Hildebrand, and others, have shown, and as I 

 can confirm, either the anthers burst before the stigma 

 is ready for fertilisation, or the stigma is ready before 

 the pollen of that flower is ready, so that these so-named 

 dichogamous plants have in fact separated sexes, and 

 must habitually be crossed. So it is with the reciprocally 

 dimorphic and trimorphic plants previously alluded to. 

 How strange are these facts! How strange that the 



