72 MUTATIONS, VARIATIONS, AND RELATIONSHIPS OF THE OENOTHERAS. 



lanceolate, tapering to the short, margined petiole, shallowly and approximately denticulate 

 above, some of them crinkled close to the midvein; terminal rosette-like cluster of the inflo- 

 rescence symmetrical and spreading; bracts lanceolate, acute, sessile or nearly so, divaricate, 

 crowded on short internodes; flowers numerous; bud club-shaped, the conic jjortion 8 mm. 

 long, 3 to 4 mm. in diameter, rarely angled, the free tips separate, quite slender, erect, 2 nmi. 

 long or less, mostly tipped with red: hypanthium 3 to 3.5 mm. long, slender, i)uberulent; 

 ovary 8 to 9 mm. long; calyx lobes one-third as long as the hypanthium; petals firm, S mm. 

 long, 9 mm. wide, deeply emarginate, cuneate; filaments 7 mm. long; anthers 4 to 5 mm. 

 long, pistil shorter than the slightly exserted stamens, the lobes divaricate, 3 to 4 m.m. long, 

 capsules abundant, 2.5 cm. long, 6 mm. in diameter at the widest portion, bluntly 4-angled, 

 pubescent, bright green, much thinner in apical portion. (The apex of some of the valves 

 are occasionally more or less distinctly bifid.) (Plate 19.) 

 Illustratioti. — Meerburg, Plantas rariores, pi. 34, 1789. 



Early in 1906 a package of seeds distributed as Oenothera parviflora was 

 received from the Botanic Garden of Madrid, Spain. The plants raised from 

 these seeds differed essentially from any of the various so-called O. biennis of 

 European origin in cultivation in the experimental grounds of the New York 

 Botanical Garden. The plants were very persistently biennial, and only one 

 or two of those placed in the open threw out lateral branches, the main branch 

 only starting its growth too late in the autumn to mature. Specimens of any 

 Oenothera closely resembling it are not to be found in the herbarium of the 

 garden or in that of Columbia University. As 0. parviflora Linnaeus was 

 credited to "Canada to Virginia" by Pursh (Fl. Am., Sept., 261, 1814), with the 

 further note that it was rare, the development of the Madrid plants was fol- 

 lowed and recorded with the hope that eventually the species might still be 

 found a component part of the North American flora. 



Late in the fall of 1905, Miss N. M. Stevens sent in some rosettes of what she 

 considered as two distinct species of Oenothera collected in the neighborhood of 

 South Harpswell, Maine. The rosettes were placed in the experiment? 1 

 greenhouse for the winter and later Miss Stevens sent seeds of both species 

 from the same locality. These latter germinated in the greenhouse and 

 though somewhat similar in the early rosette stage, one of them, the "pre- 

 vailing species" of the locality from whence the seeds came, was identified 

 with the plant determined as 0. muricata Linnaeus and the other, the "rarer 

 species" growing on sandy wastes, was identical with the species grown from 

 the Madrid garden seeds under the name of 0. parviflora, and it is from the 

 plants raised from Miss Stevens's seeds that this description has been drawn 

 (plate 20). 



The species shows distinct characteristics in color and habit. The flowers 

 are but rarely exserted beyond the bracts, which are so crowded on short 

 internodes that the ends of the branches have a closely-tufted appearance. 



The Linnaean description under Oenothera reads: "Parviflor. A. OE. fol. 

 ovate-lanceolatis planis, caule laevi subvelloso. Margo coronans jructum, non 

 uti praecedentis quadrifldus , sed octofidus." 



