46 COLIN CLOUT'S CALENDAR. 



whose rich red foliage is more likely, perhaps, to be 

 admired than the very similar leaves of the beet. All 

 these brilliant colors on spring plants are interesting be- 

 cause of the light which they incidentally cast upon the 

 origin of the equally brilliant and far more definite colors 

 of fruits and flowers. 



Those who watch trees and bushes closely must have 

 noticed that the first buds in spring are usually more or 

 less red, or at least reddish or brownish. They must also 

 have noticed that in summer the ends of long growing 

 sprays are likewise ruddy, or purple, or warm brown. 

 Now, at first sight, these facts do not seem to have much 

 connection with another class of facts, such as those 

 noticed above, of which we may take as a typical example 

 the delicate blue or violet tinge on potato-stems allowed 

 to grow in a dark cellar. But when we come to look at 

 them closely, it is clear that they have all one character- 

 istic in common : they are leaves or leaf-stems which are 

 not performing their proper functions. All plants, of 

 whatever sort, when placed in full sunlight develop the 

 active green coloring matter in their leaves the chlo- 

 rophyl which enables them to analyze carbonic acid in 

 the air, and to store its carbon as starch in their own sap 

 or tissues. When they are kept in the dark, however, 

 or when they are yet too young to have assumed their 

 proper office, they do not contain any of the green color- 

 ing matter, and so they look yellow, pink, or white. 

 The bright hue thus assumed by young or etiolated 

 leaves is due to the oxidation of their materials ; and, in 

 most cases where growth takes place from a stock of 

 food already laid by, such oxidation must necessarily go- 

 on. It is thus that we get the brilliant red, blue, and 

 yellow coloring of rhubarb, sea-kale, potato-sprouts, 

 beet-root leaves, growing peonies, or young carrots, as 



