The Vegetable Individual in its relation to Species. 195 
Campanulace, e.g. in Campanula rapunculoides. Here all 
the lateral flowers are unessential: yet if the terminal flower is 
cut off, the lateral branchlets which bear the flowers at once be- 
come essential. Such a change is not always artificial, for it often 
happens naturally, as there are plants in which the terminal flower 
may be either present or absent. Agrimonia Eupatoria, and 
Campanula rapunculoides, are examples of this variability.* 
We can cut this Gordian knot only by deciding to consider every — 
branch as an individual, however appearances may be against 
it, provided that we have other grounds sufficient to regard 
branches as individuals. ‘The genesis of branches justifies us in 
so doing ; for each branch is not a direct continuation laterally, is 
not a development belonging to the stem (like the leaf), but is a 
cen 
- Its centre of formation has been known since C. F. 
Wolff’s celebrated “'Theoria Generationis”’ (1759) under the 
name of “punctum vegetationis ;’’ it is about what is In 
* Agr imonia Eupatoria bears usually one spike without any terminal > in 
Weak specimens, a terminal flower not unfreqnently makes its eemrydiet (Bot 
pens before the upper lateral flowers. This has been observed Wydler (Bot. 
Zeit. 1844, p. 642). Campanula rapunculoides case is just the con : Its 
looser spikes are usually terminated with a flower, while denser ones el 
of bracteal leaves, without any termin r. Dietamnus resembles Agrim 
“a; while Triglochin (especially 7'r. itimum) on the other hand imitates Cam- 
panula. Even in plants in which the essentiality of the lateral position of the 
Wer 1s expressed by their zygomorphic develo te 
*ppearance in some cases; they then re “ 
obanche, anda Digital; ; (deserib d by Vrolik, Flora, 1844, No, 
1), which propagates by seeds, and is now widely disseminated in our gardens, 
