272 CONCLUDING EEMAEKS Chap. VI 



tlie 162 illegitimate seedlings in Table 36 were deriTed 

 in the course of five generations, was itseK no doubt 

 deriyed from the union of a long-styled and a short- 

 styled parent ; and the 6 short-styled seedlings may be 

 attributed to reversion to their short-styled progeni- 

 tor. But it is a surprising fact in this case, and in 

 other similar ones, that the number of the offspring 

 which thus reverted was not larger. The fact is ren- 

 dered still more strange in the particular instance of 

 P. veris, for there was no reversion until four or five 

 generations of long-styled plants had been raised. It 

 may be seen in both tables that the long-styled form 

 transmits its form much more faithfully than does the 

 short-styled, when both are fertilised with their own- 

 form pollen ; and why this should be so it is difficult 

 to conjecture, unless it be that the aboriginal parent- 

 form of most heterostyled species possessed a pistil 

 which exceeded its own stamens considerably in 

 length.* I wiU only add that in a state of nature 

 any single plant of a trimorphic species no doubt pro- 

 duces all three forms; and this may be accounted for 

 either by its several flowers being separately fertilised 

 by both the other forms, as Blldebrand supposes ; or 

 by pollen from both the other forms being deposited 

 by insects on the stigma of the same flower. 



Equal-stylei varieties. — ^The tendency of the di- 

 morphic species of Primula to produce equal-styled 

 varieties deserves notice. Oases of this kind have 



* It may be suspected that this state of nature with some flowers 



was the case with Primula, judg- on the same plant long-styled, 



ing from the length of the pistil others short-styled , and others 



in several allied genera (see equal-styled ; and the long-styled 



Mr. J. Scott, 'Journal Linn. Soc. form greatly preponderated in 



Boi' ToL viii. 1864, p. 85). Herr number ; there being 61 of this 



Breitenbach found many specimens form to 9 of the short-styled and 



rf Primula Potior growing in a 15 of the equal-styled. 



