Davis: Lamarck's evening primrose 529 



The sheet bears a label of Michaux with " Ameriq. sept." On 

 this label in the handwriting of Desfontaines is "Oenothera suaveo- 

 lens Hort. Paris." Above this name has been written "Oenothera 

 grandiflora Poiret Encycl.," and below, Spach wrote " Onagra 

 vulgaris grandiflora Spach." A second label bears the name 

 "Oenothera grandiflora," probably in the handwriting of Andr6 

 Michaux. M. Gagnepain states that the specimens were im- 

 ported as dried plants from North America. The chief interest 

 in this sheet lies in the fact that Desfontaines evidently considered 

 the specimens to be his own species Oenothera suaveolens. 



Both specimens are entire plants, the smaller about 3.5 dm., the 

 larger about 5 dm. in height. They are unbranched and ob- 

 viously dwarfed. The leaves are petioled as in grandiflora, but 

 those of the smaller plant are much below the average size for this 

 species. The stigma (5, plate 39) shown in the flower of the 

 smaller plant seems to be above the tips of the anthers as in 

 grandiflora. The pubescence of the stems and sepals, from notes 

 of M. Gagnepain, appears to be somewhat similar to grandiflora; 

 it is not that of De Vries's Lamarckiana. 



There appear to be no characters on these plants that might 

 not have been those of 0. grandiflora Solander under very unusual 

 or abnormal conditions. There is, however, little or nothing in 

 these specimens that is typical of grandiflora, and apparently 

 nothing that determines a relationship to any other Oenothera. 

 It is hardly possible that plants so different from one another grew 

 together in the same environment and it seems more probable 

 that they were quite unrelated. They remain to us as the flotsam 

 of the herbarium, plants of whose precise origin and parentage we 

 know nothing. 



Discussion 



The reader will have noted that throughout this paper the 

 name Lamarckiana has been kept strictly for the plant that has 

 come down to us from the cultures of De Vries, a plant well known 

 to scores of botanists and grown in numerous botanical gardens. 

 If this paper has shown that Lamarck's plant in the gardens of 

 Paris at about 1796 or earlier, the type of Oenothera Lamarckiana 

 Seringe (1828), was a form of Oenothera grandiflora Solander (1789) 

 the former name becomes a synonym of the latter. The Oenothera 



