202 NUTRITION 



described as reserve-substances. The proteids, starch, and oil 

 stored up in seeds are reserve-foods, to be used later on by 

 the developing seedling. Swollen subterranean stems and 

 roots are storehouses of starch {e.g. Potato), or sugar {e.g. Beet), 

 etc., which will feed the sprouting shoot in the following year. 



Nutrition of Plants possessing no chloropliyll. — Some 

 plants, such as Fungi and the Dodder, are devoid of 

 chlorophyll. Consequently they are incapable of obtaining 

 their carbon from carbon dioxide : they require supplies of 

 organic carbon - compounds. Some of these plants absorb 

 their organic food from other living plants, upon which they 

 prey. They are then described as parasites {e.g. Dodder, 

 Broom-rape). Other plants which possess no green colouring- 

 matter obtain the needful carbon-compounds from the dead 

 remains and products of plants and animals ; these are described 

 as saprophytes {e.g. Bird's Nest Orchid, Monotropd). It must 

 be noted, however, that some parasites, such as the Mistletoe, 

 and some saprophytes, have green leaves. 



