THE SEED 21 
7. Whatisbran? Does it contain any nourishment? (11, 12; Exps. 1-6.) 
8. What gives to Indian corn its value as food? to oats? wheat? 
vice? (3; Exps. 1-6.) 
9. Which of these grains has the larger proportion of endosperm to 
embryo? (Figs. 1-3.) 
10. Which contains the larger amount of nutriment in proportion to 
its bulk, rice or Indian corn? 
11. If you wished to produce a variety of corn rich in oil, you would 
select seed for planting with what part well developed? (3; Figs. 4-7.) 
IV. SEED DISPERSAL 
Mareriau. — Fruits and seeds of any kind that show adaptations for 
dispersal. Some common examples are: (1) Wind: ash, elm, maple, 
ailanthus, milkweed, clematis, sycamore, linden, dandelion, thistle, 
hawkweed. (2) Water: pecan, filbert, cranberry, lotus, hickory nut, 
coconut — obtain one with the husk on, if possible. (3) Animal agency 
(involuntary): cocklebur, tickseed, beggar-ticks, burdock; (voluntary) 
almost all kinds of edible fruits, especially the bright-colored ones — wild 
plums, cherries, haws, dogwood, persimmons, etc. (4) Explosive and 
self-planting: witch-hazel, wood sorrel, violet, crane’s-bill, wild vetch, 
peanut, medick, stork’s-bill (Erodium). 
EXPERIMENT 17. To SHOW HOW SEEDS ARE DISPERSED BY WIND. — 
Take a number of winged and plumed fruits and seeds, such as those of the 
maple, ash, ailanthus, dandelion, clematis, milkweed, and trumpet creeper; 
stand on a chair or table in a place where there is a draft of air and let 
them all go. Which travel the farther, the winged or the plumed kinds? 
Which sort is better fitted to aérial transportation ? 
EXPERIMENT 18. DISPERSAL BY WATER. — Place in a bucket of water 
a hazelnut, an acorn, an orange, a cranberry, a pecan, a hickory nut, a fresh 
apple, and a coconut with the husk on. Which are the best floaters? Cut 
open or break open the good swimmers, compare with the non-floaters, and 
see to what peculiarity of structure their floating qualities are due. In 
what situations do the cranberry and the coconut grow? Can you see 
any advantage to a plant so situated in producing fruits that float easily ? 
EXPERIMENT 19. DISPERSAL BY EXPLOSIVE CAPSULES. — Moisten 
slightly some mature but unopened capsules of witch hazel, wood sorrel, 
rabbit pea, or violet, and leave in a warm, dry place for fifteen to forty- 
five minutes. What happens when the pods begin to dry? Measure the 
distance to which the different kinds of seeds have been ejected. Which 
were thrown farthest? What was the object of the movement? What 
caused the explosion? 
