76 VARIOUS FOOD-PLANTS 
Fra. 80, 1.—Pumpkin (Cucurbita Pepo. Gourd Family, Cuwucurbitacee). 
Flowering branch. (Baillon.)—The plant is an annual climbing more 
or less by means of tendrils, and attaining a length of 7 m.; stem 
and leaves bright green, bristly hairy; flowers yellow; fruit variously 
colored in different varieties, and widely different in appearance as 
shown in Figs. 81, I-IV. 
controls the making of carbohydrates, although neither the 
iron nor the potassium enter into the product. Much of the 
process of food-making as well as of the conditions under 
which it takes place, is as yet imperfectly understood by 
physiologists. 
A living plant has been well compared to a food-factory 
where we may see the raw materials which go in and the 
products which come out, but where we can only guess as to 
what goes on inside, for on the door is written ‘No ad- 
mittance.’”’ We know that in some way the body of a plant 
is built up of highly complex materials which it makes by 
recombining the elements of relatively simple substances. 
We know also that so long as it lives the plant is breaking 
down the complex compounds into simpler ones which it gets 
