and also an obtused-leaved dwarf. The rosettes with acute pointed leaves developed plants agreeing in having foliage of narrow pointed leaves, but exhibiting a range of flower structure from that close to biennis to that of the franciscana type; 10 dwarfs characterized by sickle-shaped rosette leaves were in this group. There were several plants in the group with acute pointed leaves which presented in different respects and in varying degrees characters of Enothera Lamarckiana. The best of these Lamarckiana-like plants, 14.53c, was selected to carry forward a selfed line and its characters contrasted with those of races of Lamarckiana with which I am familiar are given below. Lamarckiana. Seedlings. Cotyledons broad at base Leaves broadly elliptical or spatu- dm. high. Long side shoots from the rosette, and side branches about midway up the central stem. Upper foliage of ovatelanceolate leaves, short petioled, crinkled. Midveins white, in some races reddish. Stems red papillate. Inflorescence. Compact and flat topped. Bracts sessile, broad at base, early in the season equaling the length of the buds, later much shorter. Buds. In large-flowered races about 8 cm. long. Cone stout, 4-angled. Plant 14.53c. Seedlings. Cotyledons similar to those of Lamarckiana. Mature rosettes. 4 dm. broad. Leaves as in Lamarckiana. Midveins white. Mature plant. Central stem 9 dm. Bracts early in season 2/3 the length of the buds. Otherwise as in Lamarckiana. Buds. 7.5 cm. long, cone somewhat less stout and less strongly 4angled. Sepals green. Sepal tips attenuate, 5-6 mm. long. Pubescence as in Lamarckiana but more dense. Ovaries with red papillæ. Petals. 4-4.5 cm. long, in some races as small as 3 cm. Stigma lobes. Usually 4, sometimes 5 or 6. Style extending 5-7 mm. above the tips of the anthers. Capsules. In some races stout and about 2 cm. long, in others more attenuate and about 3 cm. long. Petals. 3.3 cm. long. Stigma lobes. 4, rarely more. Style From this comparison of hybrid 14.53c with Lamarckiana it will be noted that the differences between the two plants were plus and minus degrees in the expression of similar characters. The most important points of resemblance were those of rosette, foliage, compact inflorescence, flower size, stigmas projecting beyond the tips of the anthers, capsule form and size (Fig. 1), pubescence in FIG. 1. Capsules of plant 14.53c, Lamarckiana-like hybrid in the F2 franciscana X biennis, compared with the capsules of Lamarckiana. general, and red papillæ over the stems and ovaries. The important differences of the hybrid were the more sprawling habit of growth of the mature plant, its bud cones less stout, and its shorter sepal tips with their heavier pubescence. There were few plants in this F2 generation Lamarckiana-like; in fact only 3 were considered worthy of attention. The evidence of segregation was clear throughout this F2 generation as shown in the great range of flower size and structure, with the extremes approaching the biennis and franciscana types, and in the varied foliage. All of the plants had the red-papillate stems of franciscana; no green stems as in biennis were represented in this culture which, however, being earth sown, probably did not exhibit the full extent of segregation possible from the F1. A culture from the sister F1 plant, 13.35ac, from seeds germinated in Petri dishes (culture 15.51) gave a small group of green-stemmed segregates (Davis 1916a, pp. 229-230). We shall see that the class of dwarfs, represented by 10 plants, appears constantly in succeeding generations, and from time to time also the hero type. Later there became more sharply differentiated the large class of plants franciscana-like in habit, foliage and bud structure. 1 THE F GENERATION. The F3 generation, culture 15.53 from the F2 plant 14.53c, was grown from 625 earth sown seeds, the contents of 4 capsules. The seed pans, kept for 7 weeks, yielded 291 seedlings, a germination That this was a low percentage and a poor germination was proved later by germinating in a Petri dish a set of only 46.6 per cent. FIG. 2. Mature rosette of the F3 plant 15.53a, neo-Lamarckiana. of 644 seeds which gave 574 seedlings, a germination of 89.1 per cent. The rosettes, as in the F2 generation, were readily separated into two groups, 91 plants with obtuse-pointed leaves and 197 plants with acute-pointed leaves; there were 3 dwarfs. In the group with acute pointed leaves 7 plants developed Lamarckiana-like rosettes and became at maturity Lamarckiana-like in other respects; From these a plant, 15.53a, was selected to be parent of the next generation and its characters are here considered and illustrated in Figs. 2, 3 and 4. With this generation I first began to use for such types the name neo-Lamarckiana. Mature rosette. Plant 15.53a, neo-Lamarckiana. As shown in Fig. 2 the mature rosette had all of the characteristics of Lamarckiana. Mature plant. Central stem well developed, at maturity 13 dm. high. The habit of the plant (Fig. 3) and its foliage were quite the same as those of Lamarckiana. Stems red papillate. Inflorescence. Compact and flat topped (Fig. 4) as in Lamarckiana. Bracts similar to those of Lamarckiana. FIG. 4. Inflorescence of F, plant 15.53a, neo-Lamarckiana. Buds. 8 cm. long. Cone (Fig. 4) more slender than in Lamarckiana, 4-angled. Sepals with faint reddish streaks. Sepal tips with heavier pubescence than in Lamarckiana but of similar character. Ovaries red papillate. Petals. 3.7 cm. long. Stigma lobes. Style extending 3 mm. above the tips of the anthers. Capsules. About 2.4 cm. long. As compared with plant 14.53c of the F2 generation plant 15.53a was closer to Lamarckiana in presenting a much better habit of growth with a tall central stem and properly arranged side shoots (Fig. 3), in better foliage now beyond criticism and in larger petals. The bud cones of the hybrid (Fig. 4) were, however, less stout and the shorter sepal tips had a heavier pubescence. |