Evening star. [volume] (Washington, D.C.) 1854-1972, 1905-12-26
MUTATIONS OF PLANTS.
May Be Induced by Agencies External
to the Plant Cells.

May Be Induced by Agencies External
to the Plant Cells.
From the New York Evening Post.
In a lecture delivered this week before
the Barnard Botanical Club. Columbia Uni
versity, upon heredity and the origin OF
species in plants, announcement Of an I'M
portant result Of his Investigations was
made by DIR. Daniel Trembly MacDougal,
lately of the New York Botanical Garden,
who has just been appointed director of the
department of botanical research, Carnegie
Institution Of Washington.
After discussing various theories and OBJ
servations in regard to the origin Of spec
les the lecturer spoke of the notable ex-
periments of Prof. Hugo De Vries In the
examination of more than 100 species OF
plants in the vicinity of Amsterdam, Hol-
land He then said:
During the last few years a partial du-
plication and an extension of these expert
ments has been carried on in New York
(by the lecturer HIMSELF. 1t seems unnee-
essary at this late date to go into the de-
tails OF the mutations of Lamarck's evening
primrose, especially since the phenomena
exhibited by them are also to be seen IN
other species. BY way of illustration II
need only be said that this plant, as origin
ally observed by De Vries, was found to
give from two to five plantlets in every
hundred which were widely divergent from
ranged in several groups, and in fact con-
stftuted Several possible species
Recent cultures in the New York Botanical
Garden from seeds of Lamarcks evening
primrose, sent from various parts of the
world where the species is under cultiva-
ton. demonstrates that 1t is not alone the
plants observed by De Vries at Hilversum
that are INITIATING, but the same deriva-
tives are being given off in widely separ-
ated localities
DR.. MacDougal announced as follows the
fact newly established by him, with his
general conclusions on the s,rbieat dis
cussed: The changes which result in the
formation of seed-mutants must ensue in
the very closing stages Of the sporophyte.
and mere is encountered feature not rec
ognized In determinations. that of a fairly
constant frequency, which In itself would
suggest internal causes. 1t was deter
mined. however, to attempt to induce or
influence mutation In one Of these periods.
Omittdng the detail Of technique,
may say that strong osmotic reagents and
weak solutions Of stimulating mineral salts
were injected into ovaries in such manner
that unfertiliZed ovules were subjected to
the action Of the fluids which killed many
OF them. but which gave the much-deslred
results In a few. In Lamarckiana and
biennis the frequency and character of the
progeny of the latter species was found a
single Individual constituting a type hither-
to unknown. This single aberrant individ-
ual might have been a mutant Of low fire.
Lamarckiana, and its recurrence here might
have been merely a matter of chance. How
ever, in another species of evening prim-
rose, Ramiannta Odorata, a flower which
belongs to separate genus Of the family,
and is not known to be INITIATING, the treat
ment described resulted in a large number
of aberrant individuals of a hitherto I'M
known type. Some of these, which show a
shorter life cycle than the parental form,
and many anatomical Emergencies, have
been brought to bloom and to maturity, and
the new form is obviously potential spe-
cies.
IN this experience exemplifed by spec
linens of the normal parental forms, and
aberrant rnutants / am able to offer you
conclusive proof that agencies external to
the cell may influence mutations. and con-
sequently exert profound Influence on
heredity. 1t would not be we'll to exag
gerate the Importance of this result, yet 1t
is evident that the establishment of this
fact marks long step forward in the ex-
perimental study of Inheritance and the
origin of SpepfeS