Davis: Lamarck's evening primrose 527 



It is exceedingly fortunate that the plant which serves as the type 

 of Oenothera Lamarckiana Seringe should have come down to us so 

 well preserved that there is scarcely a doubt of its identity with 

 Oenothera grandiflora Solander, introduced into England in 1778. 



Sheet 2. A specimen of Oenothera from the collection of 



Abbe Pourret 



This specimen (plate 38) is of interest for the reason that De 

 Vries (1901, footnote top. 317) believed that it as well as Lamarck's 

 plant agreed with the material of his cultures {"Oenothera Lamarcki- 

 ana De Vries"). Buchet (1912) has recently referred the specimen 

 to Oenothera suaveolens Desfontaines = O. grandiflora Solander. I 

 am unable to agree with either of these opinions and shall present 

 evidence that the plant was close to certain forms of Oenothera 

 biennis. 



The sheet bears the label herb. mus. paris. with the state- 

 ment at the bottom "Collection de I'Abbd Pourret, extraite de 

 I'Herbier legu6 par M. le Dr. Barbier. 1847." On this label, 

 in the handwriting of Spach are the names "Onagra vulgaris 

 Spach" and "Oenothera biennis Linn6." At the left is a list of 

 old names representing synonymy, copied by Abbe Pourret, and 

 below this list his clerk wrote the name Oenothera biennis L. 



De Vries states that the plant was probably collected by Abb6 

 Pourret in the garden of the museum at the time of his visit to 

 Paris in 1788. M. Gagnepain, however, is not satisfied with 

 the evidence for this view and writes that the history of the sheet 

 is unknown to him. 



An examination of the specimen itself (plate 38) shows the 

 following characters. 



I. Stem AND foliage. The long unbranched stem bears ellip- 

 tical, petioled leaves very different from the sessile or almost 

 sessile, broad-based leaves of De Vries's Lamarckiana. The ab- 

 sence of approximate flowering branches is against any relationship 

 to grandiflora. The appearance of the small buds in the axils of 

 the lower leaves is characteristic of some forms of Oenothera biennis. 

 The pubescence of the stem is described by M. Gagnepain as very 

 like the specimen of grandiflora and not at all like the specimen of 

 De Vries's Lamarckiana sent for comparison. 



