Meyen’s Report for 1839 on Physiological Botany. 427 
Scrophularia nodosa, aquatica, betonicefolia, peregrina, and 
vernalis; he first gives his observations on the formation 
of the placenta and of the ovulum, which agree with the 
ideas at present held on the subject. Until the formation 
of the integument the ovulum is straight, but it afterwards 
becomes bent. In Scro. betonicefolia M. Wydler remarked 
that the nucleus as it protruded from its integument be- 
came hollow, and the cavity became covered with a mem- 
brane which represented the embryo-sac ; but he could not 
distinguish whether this membrane was a new product, nor 
whether the cavity of the nucleus extended as far as the point; 
sometimes it could be distinctly seen that the end of the nu- 
cleus was closed. The description of the development of the 
stigma of the Scrophularinee is also very clear and accurate ; 
he states that the conducting tissue of the style is nothing 
more than the inner and modified epidermis of the involute 
- fruit-leaf. M. Wydler observed the fructification to take place 
by means of a pollen-tube which entered into the micropyle ; 
he also saw two or even four pollen-tubes enter at the same 
time, and correctly derives the appearance of several embryos 
from this circumstance, but adds that out of four young em- 
bryos only one comes to maturity. In regard to the act of 
~ fertilization, M. W. is evidently a follower of the new theory ; 
but he admits that he has not been able to observe the action 
of the pollen-tube when it enters into the ovulum; but on 
this the whole hypothesis depends. 
It seemed to M. W. that the embryo-sac was open at its 
end and communicated by a straight canal with the micropyle, 
for he often observed that the pollen-tube entered into the 
embryo-sac without this latter being indented. In the action 
of the seeds the presence of spiral fibres in the interior of the 
cells was observed ; in a young state the cells contained grains 
of fecula, which vanished as the seeds became ripe, and 
here and there drops of oil made their appearance, and fibres 
were formed on the inner walls of the cells. 
M. Wydler draws a number of conclusions from the above . 
observation, in which I not only do not agree, but against 
which I can bring forward important facts. Concerning the 
hypothesis that there are not two sexes in plants, and that the 
anthers may be compared to the ovarium, we have spoken at full 
in the former Report and elsewhere ; and M. W.’s observations 
on the changes which take place in the pollen-tube after its 
entrance into the nucleus are so imperfect, that we can draw 
no conclusion from them. M. Wydler has not been able to 
distinguish the pollen-tube from the supensor of the embryo; 
he speaks of the formation of cells in the former, but he evi- 
