592 thl; probable orioin of Oenothera lamarckiana ser. 



time. In this case 0. Lamarckiana must be assumed to have been 

 introduced into England about the time of Michaux and Lamarci<;, 

 and a common origin for the specimens of their herbaria and the 

 wild stations in England becomes highly probable. 



The strain of Carter and Co. has been identified by Lindley as 

 0. Lamarckiana Ser., and the high authority of this eminent botanist 

 confirms my own determination of the same strain, made by 

 comparing it with the authentic specimen of Lamarck. i) 



At all events, the adduced facts indicate a very simple history 

 of our species, which has come down to us unchanged, so far as 

 we know, from the original American habitat.^) There is no reason 

 to suppose that it originated as a garden plant, and none at all 

 to subject it to all the doubts ordinarily brought forward against 

 the purity of descent of horticultural forms in general, simply on 

 the ground that some garden plants are of known hybrid origin. 

 0. Lamarckiana has remained unchanged through more than a 

 century and has kept as true to its type as any good wild species. 

 "It is exceedingly fortunate," says Davis {op. cit. p. 527), "that 

 the plant which serves as the type of Oenothera Lamarckiana Ser. 

 should have come down to us so well preserved that there is scarcely 

 a doubt of its identity." But the identity is with the species as it 

 is still known under that name. Whether the species was in the 

 same condition of mutability at the time of its first appearance 

 as it is now, is of course a different question.^) 



Summing up the results of this historical investigation, we may 

 say: 



1. Oenothera Lamarckiana Ser. is represented by specimens in 

 the herbaria of Lamarck, Pourret and Michaux (pis. l-IH), 

 and is, so far as this material enables us to judge, at the present 

 time exactly the same plant as it was at that period. It has come 



i) Davis says (op. cit. p. 531) "the identification by Lindley of these 

 plants with O. Lamarckiana Ser. was undoubtedly incorrect," but he 

 does not give any reason for this assertion. 



2) Davis says (op. cit. p. 530) "that Lamarckiana has come down to 

 us greatly modified, that its parentage is far from pure, that it is in 

 fact of hybrid origin." This assertion which is not based upon any 

 facts is clearly contradicted by the preservation in excellent condition 

 of the three specimens of Lamarck, Pourret and Michaux, not known 

 to Davis. 



3) Uber die Dauer der Mutationsperiode bei Oenothera Lamarckiana. 

 Opera VI, p. 374. 



