506 
It is shown by M. Van Tieghem that either of these organs may be 
removed, and have the power to develop the remaining parts, so as to 
become a perfect plant. 
He has gone further than this, and shown that each of these organs 
may be subdivided into several separate parts, and each subdivision 
will grow and reproduce the organs wanting to complete the plant. 
Thus, he divided the radicle lengthwise into two parts; each part grew 
and developed the remaining, organs. The caulicle or young stem was 
likewise divided in the same manner and with the same result. Also 
each part of the cotyledons or seed-leaves, when cut into segments, 
would develop roots and buds and produce perfect plants. For example, 
the two cotyledons of a germinating sun-flower were divided each into 
‘four parts, and each part grew, making eight perfect plants. 
“In a word, any fragment will grow independently of the rest, and to 
a degree proportionate to the quantity of food stored up within itself 
at the time of ‘its separation.” 
M. Van Tieghem continued his experiments farther with a view of 
ascertaining the office performed by the albumen of seeds. The em- 
bryo of a Marvel of Peru was removed from the albumen in which it 
was imbedded. Germination took place, and growth proceeded for a 
time, but was arrested before the production of the plumule or first bud. 
Thus, it appeared that a supply of prepared food, such as the albumen 
furnishes, was necessary to the formation of the plumule. 
The next experiments were to ascertain if it was indispensable that 
this nourishment should be contained within vegetable cells. For this 
purpose the albumen was removed from the seed, pulverized, and made 
into a pulp, into which the embryo was placed. An absorption of this 
nutritive matter took place by the embryo, but not to the same extent 
as under normal circumstances. The experimenter next tried the sub- 
stitution of artificial food in place of the natural supply. An artificial 
albumen of potato-starch was made into a paste and the embryos were 
imbedded therein. Germination occurred with the absorption of starch 
grains in the same manner as in normal conditions, but only to a limited 
extent, as this artificial food was wanting in many of the constituents 
contained in the natural albumen of the plant under experiment, as 
oily materials, various salts, and nitrogenous matters, ‘hence, M. Van 
Tieghem, in pursuing his experiments, further added to the potato-starch 
a Saline solution containing nitrates and phosphates in various propor- 
tions. Under these conditions, germination progressed further than 
when starch alone was employed. When the albumen from the seeds 
of buckwheat was mashed up and used as a pabulum for the denuded 
embryo, the germination also proceeded favorably. Other experiments 
of like character with flour of wheat were not so successful, by reason 
of the rapid invasion of moulds and other microscopic organisms which 
quickly vitiated the trials.” 
These experiments may have little practical value, but they are at 
least of great physiological interest. They seem to show that, to some 
extent, the vegetable cells even of the higher plants retain somewhat 
the independent vitality possessed by the lowest forms of vegetable 
eaien 
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