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tioii. It is a little out of shape, but not especially the worse
for it.
(Plants tubes Nos. 4, 5 and 6.) Now I have two tubes
here in which the gelatin has not been laid, simply has cooled
while the tubes were in perpendicular position. I will sim-
ply make a prick culture in these, running the needle directly
into the gelatin.
(Plants tubes Nos. 7 and 8.)
Now I will place these in the incubator, the agar agar
tubes at a temperature of 98 degrees and the gelatin tubes at
a temperature of 80 degrees. The gelatin will melt down if
heated warmer than 80 degrees. It will stand, however, at
that temperature. One of the difftculties with gelatin is that
we cannot have it stand up, remain solid at a temperature
higher than about 80 degrees, and the micro-organisms of
the mouth grow very slowly at that temperature.

The Sprouting of Seeds.
In my last lecture I spoke more especially of the physio-
logical functions as they exist in the animal, and of the or-
gans and the disappearance of the organs as we pass from
the higher to the lower forms of animal life. Just in the
last sentences I spoke of the formation of alkaloids by the
higher plants and of their similarity to the waste products
of the animal kingdom; their similarity to urea, to hippuric
acid, to uric acid, etc., the similarity in chemical constitu-
tion.
I want this morning to speak more especially of the
plants, and in the study of the physiology of plants perhaps
there is no other part of the plant in which we can study it to
greater advantage than in the seed, and of the seeds the ordi-
nary grain of corn is one of the very best for that purpose. It
is large, the parts are readily distinguished with the naked
eye and it is a very favorable grain of which to make micro-
scopic sections and to study the sections. In order to study
the physiological processes we must plant the grains of corn
under conditions for germination. They may be planted in
damp sand or in damp earth, and we may take them up after
so many hours, cut sections and make the examination of
the processes going on in the grain. A very interesting series
of studies may be made by planting fifty or one hundred

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