e sporidium a circular mark, which
appears to indicate the rupture of the external membrane. From this
time another change comes over the contents. We again find the yellow
oily liquid, now occupying the external position, with some drops of
colourless or roseate liquid in the centre, so that the oily liquid
and the more limpid fluid interchange the positions which they
occupied previous to the commencement of germination. Whether these
two fluids have undergone any change in their constitution is
difficult to determine, at all events the oily liquid appears to be
less refractive and more granular, and it may be that it is a product
of new formation, containing some of the elements of the primitive
oily drop. Having regard to the delicate character of the membrane of
the germinating filaments, De Seynes supposed that it might offer
greater facility for the entrance of water by endosmose, and account
for the rapid enlargement of the sporidia. By a series of experiments
he became satisfied that this was the case to a considerable extent,
but he adds:--"I cannot help supposing that a greater absorption of
greasy matter in the cell which is the first product of germination
raises an objection to an aqueous endosmose. One can also see in this
experience a proof of the existence of two special membranes, and so
suppose that the germinative cell is the continuation of the internal
membrane, the external membrane alone being susceptible of absorbing
the liquids, at least with a certain rapidity."

[Illustration: FIG. 94.--Sporidium of _Ascobolus_ germinating.]

In other _Discomycetes_ germination takes place in a similar manner.
Boudier[P] narrates that in _Ascobolus_, when once the spore reaches a
favourable place, if the circumstances are good, _i.e._, if the
temperature is sufficiently high and the moisture sufficient, it will
germinate. The time necessary for this purpose is variable, some hours
sufficing for some species; those of _A. viridis_, for example,
germinate in eight or ten hours, doubtless because, being terrestrial,
it has in consequence less heat. The spore slightly augments in size,
then opens, generally at one or other extremity, sometimes at two, or
at any point on its surface, in order to pass the mycelium tubes. At
first simple, without septa, and granular in the interior, above all
at the extremity, these tubes, the rudiment of the mycelium, are not
long in elongating, in branching, and later in having p