Chap. VI. ON HETEEOSTYLED PLANTS. 257 



So haVe plants which inhabit alpine and lowland sites, 

 dry land, marshes and water.* 



When I first began to experimentise on hetero- 

 styled plants it was under the impression that they 

 were tending to become dioecious ; but I was soon forced 

 to relinquish this notion, as the long-styled plants of 

 Primula which, from possessing a longer pistil, larger 

 stigma, shorter stamens with smaller pollen-grains, 

 seemed to be the more feminine of the two forms, 

 yielded fewer seeds than the short-styled plants which 

 appeared to be in the above respects the more mascu- 

 line of the two. Moreover, trimorphic plants evidently 

 come under the same category with dimorphic, and 

 the former cannot be looked at as tending to become 

 dioecious. With Lyihrum saliearia, however, we have 

 the curious and unique case of the mid-styled form 

 being more feminine or less masculine in nature than 

 the other two forms. This is shown by the large 



* Out of the 38 genera known which (l.e. 43 per cent.) contain 



to include heteroatyled species, species inhabiting the just-specl- 



about eight, or 21 per cent, are fied stations. So that 43 per cent, 



more or less aquatic in their of those British plants which 



habits. I was at first struck With have their sexes separated are 



this fact, for I was not then aware more or less aquatic in their 



how large a proportion of or- habits, whereas only 21 per cent, 



dinary plants inhabit such sta- of heterostyled plants have such 



tions. Heterostyled plants may habits, I may add that the her- 



be said in one sense to have their maphrodite classes, from Monan- 



sexes separated, as the forms must dria to Gynandria inclusive, con.^ 



mutually fertilise one another. tain 447 genera, of which 113 are 



Therefore it seemed worth while aquatic in the above sense, or only 



to ascertain what proportion of 25 per cent. It thus appears, as 



the genera in the Linnean classes far as can be judged from such 



Moncecia, Dicocia and Poly- imperfect data that there is some 



gamia, contained species which connection between the separation 



five " in water, marshes, bogs or of the sexes in plants and the 



watery places." In Sir W. J. watery nature of the sites which 



Hooker's 'British Flora' (4th they inhabit; but that this does 



edit. 1838) these three Linnean not hold good with heterostyled 



classes include 40 genera, 17 of species. 



S 



