822 



THE AMERICAN NATURALIST. [Vol. XXXVI II. 



shown in Figure 6 two buds started. The series from the lat- 

 eral weak bud, 1^7-4^, are in the main like those of Figure 5, but 

 the series from the stronger bud, 1-4, show a greater accelera- 

 tion of development. The first leaf, No. i, is comparable to 

 the third leaf of Figures 4 and 5 and the third leaf of weaker 

 growth on this same plant. The second leaf. No. 2, is compara- 

 ble to tlic fifth leaf of Figure 4, and the third leaf is more com- 

 plex than anything shown in the other cases of spring growth 

 figured, hut is closely comparable to the first nepionic leaf shown 

 HI the seedling ( iMg. 3). In the localized development shown in 

 earl) s])rnig growth of weak plants, therefore, stages are found 

 which are simpler than anything found in the direct development 

 of the seedling. In vigorous plants spring growth is so much 

 accelerated that these simpler stages are not found. 



In Figures 7-13 are shown the leaves beneath the flower. Fig- 



_ • ■ ' :\i'ieal adult leaf of the stem, Figure 8 the upper 

 uit on the >teir, m tne -peennen examined. Bv comparing Figure 

 iVm-I^^'' ''^ ^^"^ seedhng(Fig. 3), it 



<- -lui t lat tne two aiv \ery similar except that the leaf tips are 

 ^''I'l"^^ ^pinitoim. lielow the flower cluster there 

 are waat are usually termed " eleft involucral bracts." These 



