90 Mr. Brown's Observations on the 
that of the parts of the calyx or corolla, enters into my notion of 
a flower complete in all its parts. 
But from this type and number of pistilla many deviations take 
place, arising either from the abstraction of part of the complete 
series of organs, from their confluence, or from both these causes 
united; with consequent abortions and obliterations of parts in 
almost every degree. According to this hypothesis, the ovarium of 
a syngenesious plant is composed of two confluent ovaria; a struc¬ 
ture which is in some degree indicated externally by the division 
of the style, and internally by the two cords which I consider as 
occupying the place of two parietal placentae, each of these being 
made up of two confluent chordulae, belonging to different parts 
of the compound organ. I am well aware how very paradoxical 
such an hypothesis must seem, especially when applied to a struc¬ 
ture apparently so simple as that of the ovarium of Compo¬ 
site; and I therefore regret that lam not yet fully prepared 
to bring forward in its support a series of facts already in my pos¬ 
session, consisting of deviations from the usual structure of organs, 
and particularly of instances of stamina changed into pistilla. 
In the mean time it may give some plausibility to the hypo¬ 
thesis to remark, that there are families of plants strictly natural 
in which a series of degradations exist, if 1 may so speak, from 
the assumed perfect pistillum, to a structure as simple as that of 
Composite. 
Thus in Proteacece we have the type of the perfect pistillum in 
the many-seeded folliculus of Embot/irium ; the first degree of im¬ 
perfection in that of Grevillea, where only one ovulum of each 
series remains; a further reduction in the indehiscent mono- 
spermous fruit of Leucospermum , in which the insertion of the 
ovulum is lateral; and the simplest form in Protea itself, where 
the 
