AND ON POLYEMBRYONY IN THE HIGHER PLANTS. 17 
known to attentive horticulturists and florists. M.DeCandolle has 
already advanced this fact*, in refutation of the views of those 
who believe that the embryo proceeds from the seminal germs of 
Gleichen (é. e. the seminal animals, or spermatozoa of the present 
day !), a view which it is well known was rather prevalent about 
the middle of the last century, and from which the new view 
of M. Schleiden differs, properly speaking, only in his allowing 
those seminal germs of Gleichen to be carried by the pollen- 
tubes into the tunics. If to this it be replied, that the produc- 
tion of hybrids can be explained as well according to the new 
view as according to the older theory of generation, the em- 
bryo-sac and its contents exercising the male fructifying action, 
—then this latter supposition must not only be repelled as 
one perfectly gratuitous, but must also be characterized as one 
which is destitute of every degree of probability. Is there the 
slightest analogy in favour of admitting that the young embryo 
penetrates into the interior of the male impregnating organ, and 
is there developed? And how then will M. Schleiden explain, 
according to this, the cases mentioned by him, where the embryo 
in an Orchideous plant is stated to have been formed on the out- 
side of the cavity of the nucleus? For what is figured as such 
is not a pollen-tube with a swelled extremity, but it is the young 
embryo with its funiculus exserted, &c. 
The greater part of that which I have here brought forward 
against the view of M. Schleiden, applies also to the new theory 
which M. Endlicher + advanced last year on the generation of 
plants. He likewise felt the insufficiency of Schleiden’s ex- 
planation relative to the male and fertilizing principle, and 
endeavoured, therefore, to perfect that theory by a different as- 
sumption. 
M. Endlicher, too, compares the anthers of the higher plants 
with the ovarium of animals; and finds the male fertilizing 
organ in the glands of the stigma, which must not be regarded 
merely as a conducting organ, but one whose peculiar secretion 
excites the pollen-grain to that activity which renders it capable 
of penetrating into the tissue of the pistil, and of arriving in the 
covering of the germ. But without any long consideration it 
will be clearly seen that this view, viz. that the stigmatic fluid 
is the fertilizing male substance, is purely arbitrary ; and since 
* Physiologie Végétale, ii. p. 546. 
+ Grundzige einer neuen Theorie der Pflanzenzeugung. Wien, 1838. 
VOL, III. PART ix. c 
