66 DEVELOPMENT OF THE FLOWER 
as well as the venation of Composite is sufficient to show that 
this may occur, though in a way not very explainable. 
‘The normal number of principal vessels of a simple pistil- 
lum is three—one midrib, two marginal; from which the 
ovula derive their vessels. 
ut this is often departed from, the pistillum may be evas- 
cular, and in many cases its venation corresponds to that ofa 
palmate leaf, Vide Nasturtium, Cucurbitacez, etc. There 
is not necessarily any correspondence between the vessels of 
the ovary and those of the style, as might be expected in all 
cases as well as in Leguminose. There is a general corres- 
pondence between the number of midribs and fascicles of 
the style, although this is often obscured, as in Anagallis 
and Limnanthes, by the occasional prolongation upwards of - 
a marginal or placental vessel. 
It follows generally in compound pistils, that the com- 
position of the pistillum is indicated by the number of vas. 
eular fasciculi of common united styles. Of this Nolana is a 
remarkable instance. 
It is only theoretically that the apparent situation of the 
stigmata can be considered as affecting the situation of the 
placenta, for the cohesion between the stigmata of com- 
pound pistilla is frequently carried to such an extent as 
completely to obscure the original lines of separation.* 
know of no instance in which the placental vessels arise 
from the midrib ; they have an independent origin. Although | 
in the generality of cases there is obviously a sinus in simple- 
pistil stigma, or a perforation with a confluency of all these 
sinuses, yet in many cases no trace of convolution is to be 
found in the stigma, which is the absolutely terminal point, 
arising both from the mares of the style and the conduct- 
ing tissue. 
There is nothing definite in the amount or limits of stig- 
matic surface ; gebesiis. in cases of linear surfaces, it will be 
found spread over the inner face of the style in laminate stig- 
mata, but remarkable exceptions occur in some Acanthaces. 
* Herea s occurs in the MS. and what follows between brackets is pa 
written in pene 
