FERTILIZATION. 265 
way of application of the pollen to the stigma may be, its 
effects are much diminished by the ease with which the 
subsequent operations are completed ; vide Mr. Brown’s re- 
marks. Again how is the universal presence of the pla- 
cental chords and their invariable bifurcation so as to supply 
each side of the placenta, explainable. 
In Dr. Lindley's Introduction 2nd Edition, the Bauerian 
theory is adopted : moreover, it is given in the essential charac- 
ter, in which nothing that is not proved by observation, should 
ever be admitted. In the commencement of the Ist Paragraph 
after that of Affinities, the description of the stigma will be 
found, and it is stated that it is through a of “ callosity’? 
that the fecundating matter passes into the tissue communi- 
cating with the ovules. On this I have only to remark, that 
the passage of the fecundating tube invariably takes place 
through the softest tissue of the vegetable organization. And 
that in Orchidez, this tissue often consists of elongated cells 
imbedded in mucus? So that the passage througha callous 
point is not only contrary to analogy, but involves the neces- 
sity of two sorts of tissue of communication, of a diametri- 
cally opposite nature, one of which too, may be considered 
as the type of ordinary stigmatic tissue. 
The phenomena of impregnation cannot be too often ob- 
served in this family, in which there occur several distinct 
modifications of the pollen, all well worthy of minute study 
in connection with the form and situation of the female 
organ. 
If complication be, as I believe it will be found, a sign of 
perfection, Orchidee are the most perfect of monocotyle- 
donous plants. They form a most natural family, and one 
of very great extent, their applicabilities to diversities of cli- 
mate and situation are very great. 
They present a decided analogy with Dicotyledons, in the 
articulation of their leaves, and the hard texture of these. 
The almost universal irregularity of the perianth, may also be 
considered as a sign of perfection, : 
I 
