MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 189 



about 2 to 5 internodes of a thickness not more than one third of the 

 etiolated, and a total length of not over 5 cm., the maximum length 

 of single internodes being less than 5 cm. Etiolated branches 

 developed 6 to 8 internodes, or about the same as juvenile sprouts, 

 the maximum length of the internodes being about 14 cm., which 

 was double that of the juvenile sprouts. 



After the above growth had been made in darkness, the terminal 

 buds perished, and activity was generally begun by the buds on the 

 basal portion of the etiolated twigs, although some were developed 

 on the terminal portions. It was noticeable that the greater number 

 of buds on etiolated twigs that awakened were exposed to the 

 occasional illumination of the gaslight by the aid of which exami- 

 nations were made. In one instance an etiolated shoot showed a 

 development of all of the main axillary buds on the illuminated side, 

 and none on the other. The etiolated twigs bore pairs of opposite 

 leaves, the petioles of which had a length of about 2.5 to 4 cm., and 

 the small laminae measured 2 by 1.5 cm. being extended, and about 

 one sixth of the normal size. (See Fig. 148.) 



Fig. 148. Acer rubrum. A, etiolated branch with leaves. B^ normal greenleaf. 



The anatomical changes which may be ascribed to the effects of 

 etiolation in Acer were more nearl}^ parallel to Corniis than to 

 ^uercus or Hicoria. The subepidermal layers of cork were present, 

 and the formation of lenticels had begun in the basal internodes of 

 the etiolated stems. Such lenticels were larger and more numerous 



