lOO 



MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 



reached an advanced stage, and was followed by some discoloration 

 of the epidermis. 



Normal stems of the same age showed no indications of the 

 formation of phellogen. The cortical cells were smaller than in 

 the etiolated with the tangential greater than the radial diameter. 

 The bast cells were much like those of the etiolated stem. A region 

 immediately underneath the epidermis contained much chlorophyl, 

 which also extended down into the pith through the rays. No 

 marked differences in the trichomes could be found. 



Cyclamen sp. 

 Corms of Cyclamen purchased from a dealer were placed in moist 

 soil in the dark room in January, 1900. The growth of the leaves 

 soon began, and elongated petioles were formed, which were soon 



D 



Fig. 55. Cyclamen. A, normal epidermis. B, etiolated epidermis. C, etiolated 

 hairs, from the petiole. D, normal hairs from petiole. Terminal portion of petiole 

 with etiolated lamina. 



