THE ORIGIN OF ANGIOSPERMS. 39 
who have already upheld the view maintained here. Goebel?, in particular, 
regards the amphisporangiate condition as primitive, and the monosporangiate 
as derived from it. 
It will be necessary here to examine somewhat at length the evidence for the 
assumption that certain naked flowers may be regarded as primitive, and the 
consequent corollary that their near relatives, with insignificant perianth, are 
derived from them. 
The main departure of Engler’s and Eichler's systems of classification from 
that of Bentham and Hooker consists in the abolition of the large group 
Monochlamydez or Incomplete, and the distribution of its families among the 
Polypetale, making one large series, the Archichlamydez ог Choripetale ; 
without question a move in the right direction. At the same time both Engler 
and Eichler cease to regard the Ranales (Polycarpice) as the starting point of 
existing Dicotyledons. They commence their systems with plants possessing 
flowers composed of few parts, especially the Piperaeez and its near allies, 
and also with the Amentiferous families. Their scheme of classification then 
gradually advances from plants with naked flowers to others possessing an 
insignificant sepaloid perianth, and finally to such orders as the Caryo- 
phyllaceze with a well-marked calyx and a conspicuous corolla. From this 
point of view, the gradual evolution and differentiation of а perianth can be 
traced in a general way. 
Three objections of considerable weight can be advanced against this theory. 
In the first place, it must be assumed that the perianth is evolved de novo, and 
is an organ sui generis. Secondly, in many of the groups regarded as primitive, 
e.g., Piperales, Amentiferze, and Pandanales, the inflorescence is a sharply 
defined and often a highly complicated structure. Lastly, such a theory has 
so far proved barren from a phylogenetic standpoint, especially when the 
attempt is made to bring into line evidence derived from the study of fossil 
plants. 
We may now briefly examine the cohorts which Engler regards as showing 
primitive features. 
Piperales. 
This cohort is placed first in Engler and Prantl’s system, and includes four 
orders, of which only the Piperaceæ is well represented by the species of 
two genera Piper and Peperomia. A survey of its members suggests that its 
flowers are fashioned, for the most part, on the trimerous plan, with two whorls 
of stamens and three carpels. No one would argue that a species of Piper 
with only two stamens has preceded one with six, nor that one with three 
carpels has been derived from an ancestor with a single carpel. Nor is it to be 
supposed that a genus like Chloranthus, with a sin gle tepal, has given rise to one 
* Goebel (1905) p. 528. 
