• Webster's Revised Unabridged Dictionary
    • n Weismannism (Biol) The theories and teachings in regard to heredity propounded by the German biologist August Weismann, esp. in regard to germ plasm as the basis of heredity and the impossibility of transmitting acquired characteristics; -- often called neo-Darwinism.
    • ***
Century Dictionary and Cyclopedia
    • n Weismannism The opinions and teachings of August Weismann, a noted German zoölogist and writer on speculative biology. In a memoir on the origin of the sexual cells of hydroids (1883), he showed that the sexual cells which undergo their development in the gonophores of certain hydroids are present, and recognizable, long before the gonophores, the blastostyles which carry them, or the hydranths which carry the blastostyles, come into being; and that the germ-cells reach their destination by long and complicated migrations along definite lines or germ-paths. He was afterward led, by reflection upon these facts and others, to the system of speculations about the nature of inheritance which is known by his name. These consist of the doctrine of germ-plasm together with the logical consequences of its acceptance. Germ-plasm is held to be the substance of inheritance, endowed with a complicated architecture, and never formed anew, being handed down from generation to generation in unbroken continuity. Among the logical consequences, real or assumed, of belief in this theory are: belief that germ-plasm, germ-cells, and unicellular organisms are potentially immortal, or independent of or exempt from natural death; that the development of multicellular organisms always is, has been, and must be, evolution or unfolding of the preexistent; that cell-division is differential, consisting of the division of a cell into two or more with unlike values in inheritance and with unlike predetermined fates; that inheritance is due to the continuity of germ-plasm; that the somatic cells, or those which enter into the composition of the body, are out of the line of descent to future generations and subject to natural death, and that modifications produced in the soma (“acquired characters”) are not and cannot be inherited by descendants, because the somatic cells have no descendants; that certain somatic cells serve as the bearers of germ-plasm along definite cell-paths to the regions of the body where new germ-cells are to be formed; that new hereditary modifications arise only in the germ-plasm through new combinations in sexual reproduction or amphigony; and that among these those that are fittest are preserved according to the principle of natural selection, which is the only and all-sufficient ground of the origin of species.
    • n Weismannism In popular biological literature, the doctrine or opinion that acquired characters are not, and can not be, inherited. See doctrine of germ-plasm, substance of heredity, acquired character.
    • ***
Chambers's Twentieth Century Dictionary
    • n Weismannism vīs′man-izm the doctrine in biology of August Weismann (born 1834)—that acquired characters are not transmitted, function and environment affecting the individual only, not the species, the sole source of evolutionary change being the intermingling of germ-plasma which occurs in fertilisation, and the condition of progress being found in the action of natural selection on the germinal variations which thus arise.
    • ***


In literature:

There you have the three great schools which divide modern evolutionists: Lamarckism, Weismannism, and Mendelism (or Mutationism).
"The Story of Evolution" by Joseph McCabe
During this period nevertheless one distinct advance was made, that with which Weismann's name is prominently connected.
"Darwin and Modern Science" by A.C. Seward and Others
"The Life and Letters of Charles Darwin, Volume II (of II)" by Charles Darwin
This is the same Weismann who rendered so many important services to Russia, during the last war with the Turks.
"The Life and Adventures of Baron Trenck Vol. 1 (of 2)" by Baron Trenck
Have you seen Weismann's pamphlet "Einfluss der Isolirung," Leipzig, 1872?
"More Letters of Charles Darwin" by Charles Darwin
I am, however, glad to find that Prof. Weismann has some faith in this principle.
"More Letters of Charles Darwin Volume II" by Charles Darwin
Mr. Wallace, therefore, may well be excused if he casts longing eyes towards Weismannism.
"Essays on Life, Art and Science" by Samuel Butler
Mr. Wallace, therefore, may well be excused if he casts longing eyes towards Weismannism.
"The Humour of Homer and Other Essays" by Samuel Butler
In 1903, Weismann's theory of the continuity of the germplasm was ten years old.
"Taboo and Genetics" by Melvin Moses Knight, Iva Lowther Peters, and Phyllis Mary Blanchard
The researches of Dr. Weismann illustrate this progressive adaptation.
"Darwinism (1889)" by Alfred Russel Wallace

In news:

When a thief bashed a passenger side window of Jason Weismann's car, they stole an iPad and a cloth bag filled with binders of handwritten notes.
And Weismann couldn't care less about the iPad.
Weismann talks to b about hoop dancing, her crush on Mike Rowe and more.
Jason Weismann, who lives in Richfield, says he wants his lifetime of work returned.
Last Thursday in Roseville, someone bashed in a window of Jason Weismann's car and stole an iPad and a cloth bag filled with binders of handwritten notes.
When a thief bashed a passenger-side window of Jason Weismann's car, they stole an iPad and a cloth bag filled with binders of handwritten notes.

In science:

Weismann at the end of the 19th century suggested roughly that we die to make place for our children.
The Penna Model of Biological Aging