CHAPTER VIII. FRUITS 
I. HORTICULTURAL AND BOTANICAL FRUITS 
Marerra. — Green ears of corn or wheat, fresh pods of beans, young 
fruits of apple, grape, tomato, melon, buckeye, chestnut, or pecan. A 
young fruiting stem of squash, gourd, or tomato. 
Apptrances. — Coloring fluid, glasses of water, a piece of cardboard, 
tin-foil, vaseline. 
ExpERIMENT 87. WHERE DO THE FOOD SUBSTANCES CONTAINED IN 
FRUITS COME FRoM? — Apply your food tests to the pulp of a young apple, 
squash, bean pod, chestnut, buckeye, or a ‘‘green” ear of corn or wheat, 
and see what it contains. Test the stem and roots of a plant of the same 
kind in the same way. Do you find the same foods in them? Where 
is the food stored? 
ExprERIMENT 88. THROUGH WHAT PARTS OF THE STEM AND FRUIT DO 
WATER AND NOURISHMENT TRAVEL TO THE SEED ? — Cut a young squash 
or cucumber from the vine, leaving stem enough to insert by its cut end 
in a glass of eosin solution. Leave for two or three days, then make a 
vertical section through the stem and fruit. What course has the liquid 
followed? Can you trace some of it into each seed? Do you see now a 
use for the seed stalk and the rhaphe? 
EXPERIMENT 89. DoES THE SURFACE OF FRUITS GIVE OFF WATER BY 
TRANSPIRATION ? — Try Exp. 59, using in place of leaves a young squash, 
eggplant, or a bunch of grapes, and after a day or two notice whether 
any moisture has been given off. If the fruit skin gives off moisture, 
it is natural to expect that it would be provided with stomata, like other 
transpiring organs. To find out whether this is so, place a thin piece of 
the outer epidermis of a grape, tomato, plum, or apple under the micro- 
scope. Do you find stomata on any of them? Do you see anything else? 
Try the skin of an apple, and compare the corky dots you find there with 
those on the bark of a young dicotyl stem (118) and decide what they are. 
EXPERIMENT 90. WILL FRUITS RIPEN WELL IN THE ABSENCE OF LIGHT 
AND AIR? — Envelop a number of immature fruits in bags of dark cloth 
or paper so that no light can reach them. Keep a number of others well 
coated with oil or vaseline, and watch. Do the fruits so treated mature 
as quickly or develop as fully as those of the same kind left untreated ? 
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