88 THE JOURNAL OF BOTANY 



viduality under the very variable ecological conditions of the 

 dunes indicates the attainment of a high degree of fixity of 

 character. Notwithstanding the variations pointed out, we are 

 still of opinion that on the dunes its diagnostic characters are 

 never so obliterated as to render it unrecognisable. When the 

 conditions of growth are normal, the plants may be seen growing 

 in hundreds, and showing little or no variability. 



Mr. Melvill suggests the desirability of cultural experiments 

 in order to test its permanence and its status. As to its 

 permanence under its proper environment, w y e adduced evidence 

 in our previous paper of the long existence of the plant in its 

 present form. The cultivation of all new varieties for several 

 years before being described is, however, a counsel of perfection 

 which has not always been observed in the past, and will 

 probably never in the future become a universal rule. Such 

 a proceeding would, perhaps, be most necessary where a few 

 odd plants showing variation occurred amongst a crowd of 

 normal ones. The var. condensate,, to our personal knowledge, 

 occurs in a long tract of country extending into three counties, 

 and in no instance have we seen it assume the appearance of 

 the type. It is not an easy plant to cultivate, but one of us 

 has succeeded in getting it to seed in a plant-pot filled with 

 sphagnum, standing in a dish constantly supplied w T ith water. 

 It did not thrive well, and never seemed really healthy, probably 

 because of the absence of mineral salts. The flowers were small, 

 but otherwise it retained the habit of var. condensata. Our plant 

 came under the observation of the botanists taking part in the 

 International Phytogeographical Excursion, and we have learned 

 since putting together our previous notes that Prof. Graebner, 

 impressed by its distinct appearance, took examples to grow in 

 his Berlin garden. According to Mr. Druce, in the New Phyto- 

 logist, up to date it had maintained its characteristic features. All 

 these points afford strong presumptive evidence of its permanency. 



The question of its status raises a very debatable subject 

 indeed, on which each individual botanist may be expected to 

 have diverse opinions. If we grant the existence of plants 

 somewhat intermediate between the variety and the type, it 

 will hardly be contended in these days that the existence of 

 sucli connecting links extinguishes the claim of the former 

 to varietal rank. If this were so, very few varieties at present 

 widely accepted would stand the test. Mere erratic abnormalities 

 and accidental pathological states have, even in recent times, been 

 accepted as good varieties by eminent botanists. P.palustris var. 

 condensata does not belong to that category. We regard it as a 

 descendant of the typical plant, wmich became isolated in its 

 present situation as thoroughly as if on an island, where it has 

 undergone modification by the combined influences of the peculiar 

 ecological conditions of the dunes, the mild climate, and constant 

 inbreeding, until its divergences from the ordinary plant have 

 become sufficiently marked and fixed as to render it recognisable 

 as a variety. 



