Weismann (Frankfort, 1850) and by C. Kinzel (Halle, 1884); the Alexandreis of Gaultier de Lille, by F.
The next step is illustrated by the female gonophores of Cladocoryne, where the radial and ring-canals F G H Modified from Weismann, Entstehung der Sexualzellen bei den Hydromedusen.
Weismann.) I, Ideally primitive method of budding, in which the mouth is formed first (Ia), next the tentacles (Ib), and lastly the umbrella.
Weismann, Die Entstehung der Sexualzellen bei den Hydromedusen (Jena, 1883); 59.
Weismann and Hugo de Vries.
Rep. 1899; Wallace, Darwinism; Weismann, The Germ-Plasm.
Was not at first recognized and the true nature of imaginal disks was not at first perceived, even by Weismann, to whom their discovery in Diptera is due.
Weismann (1863-1864) traced details of the growth of embryo and of pupa among the Diptera, and A.
By August Weismann (memoirs translated by Meldola) by Edward B.
Weismann has also ingeniously argued from the structure of the egg-cell and sperm-cell, and from the way in which, and the period at which, they are derived in the course of the growth of the embryo from the egg - from the fertilized egg-cell - that it is impossible (it would be better to say highly improbable) that an alteration in parental structure could produce any exactly representative change in the substance of the germ or sperm-cells.
Thus the occurrence of blind animals in caves and in the deep sea was a fact which Darwin himself regarded as best explained by the atrophy of the organ of vision in successive generations through the absence of light and 1 Weismann, Vererbung, &c. (1886).
Trans., London, 1899); Weismann, Essays upon Heredity (Eng.
1894, A Rejoinder to Professor Weismann and Weismannism once more.
Weismann, Lady Verney) have shown by experimenting upon birds that this suggestion is correct; and Guy Marshall found that baboons which are afraid of snakes are also afraid of the snake-like larva of the South African Chaerocampa osiris.
Weismann, The Evolution Theory, Eng.
Weismann, however, from theoretical considerations and from analysis of supposed cases has at the least thrown doubt on the transmission of acquired characters.
The conceptions of Weismann afford no ground for rejecting fluctuating variations from the materials for the production of species.
Weismann, The Evolution Theory (London, 1904); W.
Weismann, however, doubts these conclusions, and having found a spermaster in every one of the eggs that he examined from workercells, and in only one out of 272 eggs taken from drone-cells, he supports Dzierzon's view, explaining the single exception mentioned above as a mistake of the queen, she having laid inadvertently this single fertilized egg in a drone instead of in a worker cell.
Darwin died some years before the controversy upon the possibility of the hereditary transmission of acquired characters arose over the writings of Weismann, but Wallace has freely accepted the general results of the German zoologist's teaching, and in Darwinism has presented a complete theory of the causes of evolution unmixed with any trace of Lamarck's use or disuse of inheritance, or Buffon's hereditary effect of the direct influence of surroundings.
Weismann, all the leading biologists had either subscribed to the telegony doctrine or admitted that "infection of the germ" was well within the bounds of possibilities.
Even Professor Weismann did not deny the possibility of the offspring throwing back to a previous mate.
In assuming this attitude Professor Weismann decidedly differed from Herbert Spencer, who some years ago mentioned that he had evidence "enough to prove the fact of a previous sire asserting his influence on a subsequent progeny."