520 Davis: Lamarck's evening primrose 



my own collections and at the New York Botanical Garden, was 

 unmistakable. Miss Alice Eastwood, who kindly looked up 

 various matters for me during her recent trip abroad, examined 

 last winter in Paris this sheet which stands for the type of Oenothera 

 Lamarckiana Seringe and reported to me her belief that it is identical 

 with 0. grandiflora Solander. As a result of this report I obtained 

 through the courtesy of M. Frangois Gagnepain negatives of this 

 and other herbarium sheets at the Museum d'Histoire Naturelle 

 bearing upon the problem. M. Gagnepain further has most 

 kindly answered a number of specific enquiries concerning the 

 history of the specimens and certain characters of the plants not 

 shown in the photographs. The following descriptions of these 

 herbarium sheets are then in part from the photographs here 

 published and in part from the notes of Miss Eastwood and M. 

 Gagnepain, to whom I am greatly indebted. 



The three sheets, to be described, were examined by Professor 

 De Vries, who has given his interpretation (1901) in footnotes to 

 Die Mutationstheorie, Vol. I, pp. 316, 317. De Vries believed that 

 the first two sheets agreed with his cultures of Lamarckiana. The 

 specimens on the third sheet he referred to Oenothera grandiflora 

 Alton (0. suaveolens Desfontaines) = 0. grandiflora Solander. 

 The conclusions of the present paper are (i) that the first sheet 

 (plate 37), the type of Oenothera Lamarckiana Seringe, shows a 

 remarkably well preserved and characteristic specimen of Oenothera 

 grandiflora Solander, (2) that the specimen on the second sheet 

 (plate 38) is neither 0. grandiflora Solander nor "0. Lamarckiana De 

 Vries " but a plant that is close to certain forms of 0. biennis, and 

 (3) that the two plants on the third sheet (plate 39), obviously 

 stunted in growth, are so imperfect that an opinion of their identity 

 can hardly be more than a guess. Our interest in this herbarium 

 material centers upon the first two sheets. 



Sheet i. Lamarck's plant, which stands as the type of 

 Oenothera Lamarckiana Seringe 

 This specimen (plate 37) is in the herbarium of Lamarck, 

 acquired by the Museum d'Histoire Naturelle in 1886. The 

 sheet bears in the handwriting of Lamarck: "Oenothera . . . 

 [grandiflora] . . . nova spec, flores magni lutei, odore grato, caulis 



