The following are a few of the more general works: Bateson, Materials for the Study of Variation; Bunge, Vitalismus and Mechanismus; Cope, Origin of the Fittest, Primary Factors of Organic Evolution, Darwin's Life and Letters; H.
Further references of great value will be found in the works of Bateson and Pearson referred to above, and in the annual volumes of the Zoological Record, particularly under the head " General Subject."
Bateson and M.
In 1883-1886 Bateson showed by his embryological researches that the Enteropneusta exhibit chordate (vertebrate) affinities in respect of the coelomic, skeletal and nervous systems as well as in regard to the respiratory system, and, further, that the gill-slits are formed upon a plan similar to that of the gillslits of Amphioxus, being subdivided by tongue-bars which depend from the dorsal borders of the slits.
On account of the presence and mode of origin (from the gut-wall) of this organ Bateson introduced the term hemichorda as a phyletic name for the class Enteropneusta.
In the direct development Bateson showed that the three divisions of the coelom arise as pouches constricted off from the archenteron or primitive gut, thus resembling the development of the mesoblastic somites of Amphioxus.
Bateson, "Memoirs on the Direct Development of Balanoglossus," Quart.
Bateson has shown this to be the case for the sweet-pea (Lathyrus odoratus), var.
Bateson considers that the purple colour is due to the simultaneous existence in the plant of two colour factors which may be designated by C and R.
Bateson, Mendel's Principles of Heredity, a Defence (Cambridge, 1902); W.
Bateson and E.
See Edward Bateson and A.
Bateson and H.
De Vries gave the name "mutations" to such considerable variations (it is to be noted that a further concept, that of the mode of origin, has been added to the word mutation, and that the conception of relative size is being removed from it), and Bateson, de Vries and other writers have added many striking cases to those recorded by Darwin.
The variations which de Vries has called mutations, and which were at first associated by Bateson with what he called discontinuous variations as the exclusive source of new species, are now supposed by de Vries to be distinguished from fluctuating variations by their mode of origin.
Bateson is pre-eminent, would appear to simplify the problem of variation, especially on its mechanical and physiological sides.
Bateson, Mendel's Principles of Heredity (Cambridge, 1909); E.