306 Blodgett : Vegetative Reproduction 



The mature bulbs are usually in good flower about the middle 

 of April, and the seeds ripen in June. They must be looked for 

 among the leaves upon the surface of the ground, as the entire 

 plant becomes withered and prostrate soon after the fall of the 

 flowers. The ripe seeds are about 6 mm. long, half as wide, and 

 in shape resemble, distantly, a segment of an orange, on account 

 of a prominent raphe and spur along one side (Fig. i). In tex- 

 ture the seed is firm and hard ; in color, brown darkening with age 

 and exposure. The surface is strongly convex, and smooth, 

 though hardly shining. The raphe and spur are absent in seeds 

 which have lain in the soil over winter. In Erythronium Dens-cams 

 the raphe is less developed, the spur is present as a slender curved 

 hook or beak from the apex of the seed.* 



The seeds remain dormant for nine months — from June to 

 April, when they germinate (Fig. 4), reaching their best develop- 

 ment as seedlings (Fig. 7), about the time that the flowers are in 

 their prime. The young plant elongates in opposite directions : 

 the upper end, the tip of the cotyledon, contains a gland (Fig. 6,g) 

 by which the food substance of the seed is absorbed. The lower 

 end is protected by a root cap during the first stage of its growth. 

 While the tip of the cotyledon advances the length of the seed, the 

 opposite end penetrates the soil for an inch or more. About the 

 time that the food is absorbed from the seed and the cotyledon 

 frees itself from the empty testa, the descending part changes also. 

 From one side of this portion, close to the tip (r, Fig. 5), the rad- 

 icle is produced, and penetrates farther into the soil. It is plenti- 

 fully supplied at its base with root hairs (Fig. 9). 



The cotyledon is supplied, for the greater portion of its length, 

 with stomata, and functionally it is a cylindrical leaf. Starch is 

 scattered through it, being in all portions of the tissue at a (Fig. 

 23), mostly epidermal in the guard cells of the stomata at b, usu- 

 ally near the fibrovascular bundles at r, and general again at d. 

 Close to the tip (d) there is a local deposit of starch, as if pro- 

 vided for the growing cells just within the root cap (5, Fig. 5). 

 The part from which the radicle springs enlarges, becomes charged 

 with starch, and forms a bulb (Fig. 9), which is usually forced 



*Irmisch : Beitrage zur verg. Morphologie der Pflanzen. Abhand. d. Natur. Gesell. 

 zu Halle, 17 3 : 184-195. 1863. 



