1879] TRANSACTIONS. 5 



leaves and blossoms, and all the parts of every blossom, are 

 only modified forms of one or more of the four parts or mem- 

 bers just spoken of. This is the statement, made abruptly and 

 in few words, of the accepted theory of plant structure." In a 

 seedling, how many times are parts which are made up of a 

 joint of stem and a green leaf, or a pair of them, repeated } In 

 one seedling, there will be found six or more of these repeated 

 parts ; in another, only two or three, in another, perhaps only one 

 besides that previously existing as the germ itself. The 

 " repeated parts " differ greatly in their shape and size, and also 

 in their kinds of work. 



" Now these ' repeated parts ' are helping parts or helpful 

 parts. These parts are mutually helpful : they help one another. 

 The whole plant is made up of just such parts, which have 

 taken different forms for different kinds of work ; as, for 

 instance, in the leaves of the pea. 



The seedlings of garden plants show these helpful parts, 

 arranged in regular order. From the lowest of the helpful 

 parts of the bean, the root started ; but, in the Indian Corn, 

 roots have started off also higher up. Again, they have plant- 

 hairs in different places. Upon the youngest rootlets of the 

 wheat or corn planted on wet paper, the hairs are very 

 abundant ; and there are some hairs scattered on the leaves 

 of the bean. These roots and the hairs are to be examined 

 later. 



The succession of the helpful parts will be noticed best in 

 slips of the common plants, " Wandering Jew," or Tradescantia, 

 Heliotrope, and Bouvardia. In the case of the Tradescantia, 

 the growth of a slip or cutting in moist sand, or with the lower 

 end in water, is very instructive : roots grow from the lowest of 

 the helpful parts, and furnish the food needed in solution, new 

 leaves expand above to get food, as we shall see, from the air ; 

 and thus a separate, self-supporting colony is established. A 

 flowering plant is a community from which many such colonies 

 might be removed. 



Next, arises the question : Where do these helpful parts 

 come from } Of course, from buds. A bud is the promise of 

 a branch. The application of this to the case in hand will force 

 the conclusion that, since whatever springs from a bud is some 

 sort of a branch, a developed flower from a flower-bud must be 

 a branch too. And so it is. The helpful parts are here arranged 

 in a very regular manner, and many of them are greatly changed 

 in form and in work. From this subject, to be examined fully 



