114 EXPERIMENT STATION RECORD. 



light show increased size and a particular coloring; and that those 

 from the green and blue hothouses and under very feeble light have 

 lost almost all their resemblance to the normal leaf. These experiments 

 establish the fact that light, without the aid of any other factors, is 

 able to modify plants. 



Results not less curious have been obtained with other plants, some 

 of which are shown in the colored plate (PI. II). The red flowered 

 crassula was placed in the dark at a time when its buds were only 

 slightly colored. It shows only a narrow, colored edge bordering a 

 white flower. The purple leaves of Alternanthera amena became abso- 

 lutely green under the red glass. Geranium leaves lost their reddish- 

 brown tone and changed under the red, blue, and green rays into the 

 three following forms: In the red hothouse they were large, well cut, 

 and pale green ; in the blue, almost round and dark green ; in the green, 

 small and very pale green. Similar experiments were made with fruits 

 by surrounding the branches with colored glasses. The same results 

 as indicated above were produced with peaches, apples, cherries, aud 

 strawberries. In certain plants the leucites, to which their coloration 

 is due, act according to the way in which they receive the light. Others 

 vary under the influence of light in combination with the plant's nutri- 

 tion. Still others are altogether insensible to the action of light. To 

 the last class belong carrots, beets, radishes, potatoes, truffles, etc., the 

 underground colorations of which are evidently independent of light. 



[Concluded in next number.] 



