THE 
New Phytologist 
Vol. XVIII, Nos. 3 & 4 . March & April, 1919 . 
[Published May 14th, 1919.] 
THE ORIGIN AND DEVELOPMENT OP THE 
COMPOSITE. 
By James Small, M.Sc. (Lond.), Ph.C. 
Chapter XI. 
THE ORIGIN OF THE COMPOSITE. 
I N the previous chapters phylesis has been studied by the 
methods of comparative morphology, and a comparison of 
the details of the movements of the styles and stamens has 
been added. The conclusions arrived at have been tested by the 
geographical distribution of the groups (Chap. X). The phyletic 
data which have been elucidated would seem to support the origin 
of species by mutation and by the direct action of environment. 
Evidence is also given of the action of the Age and Area Law and, 
to a certain extent, the Differentiation Theory of Guppy is sup¬ 
ported. It appears that Natural Selection has acted only on broad 
lines, such as the large development of Compositze in the best 
situations for the dispersal of the fruits, and the selection of the 
mountain ranges as the path of migration. 
In view of the multiplicity of evolutionary theories at the 
present time it is necessary to examine these and to endeavour to 
state precisely the evolutionary theory which appears to be most in 
accordance with the results of the present study before proceeding 
to any detailed enquiry on the actual origin of the family. The 
problem of this origin has four main facets—(1) From what group of 
plants did the family arise ? (2) By what method ? (3) In what 
region ? (4) At what geological time ? The first three points are 
discussed in the present chapter, the second being taken before the 
others in order to make the discussion of the first problem more 
circumscribed and precise. A brief summary of previous views on 
the origin of the family is given in the first section. 
A. History. 
t 
Linne (I, 59, p, 415) classed Dipsacus and Jasione with the 
Compositze in his “ Communes ” and later (I, 59, p, 441) he placed 
