How does Mutation theory of Dev. Vries differ from Lamarck and Darwin's view in the origin of new species.

Explanation

Mutation theory
(i) Hugo de Vries put forth the Mutation theory. Mutations are sudden random changes that occur in an organisms that is not heritable. De Vries carried out his experiments in the Evening Primrose plant (Oenothera lamarckiana) and observed variations in them due to mutation.
(ii) According to de Vries, sudden and large variations were responsible for the origin of new species
Salient features of Mutation Theory
(i) Mutations or discontinuous variation are transmitted to other generations.
(ii) In naturally breeding populations, mutations occur from time to time.
(iii) There are no intermediate forms, as they are fully fledged.
(iv) They are strictly subjected to natural selection.
(a) Lamarck and Darwin believed in gradual accumulation of all variation as the causative factors in the origin of new species.
(b) Further Lamarck believed that characters developed during the life time of an organism are called acquired characters and these are then inherited.
Darwin did not distinguish between somatic and germinal variation and attributed Natural selection as the force for origin of new species.