76 



VARIOUS FOOD-PLANTS 





Fia. 80, I. — Pumpkin {Cuciirbita Pcjto. Gourd Family, Cucurbitnccac). 

 Flowering branoh. (Baillon.) — Tho 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 3'et imperfeetlj^ understood by 

 physiologists. 



A living plant has been well compared to a food-factor}^ 

 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 



