510 



THE AMERICAN NATURALIST [Vol. XLIII 



e is now evident 

 H. Morgan. 



i.itkkatu;;: 



Allen. G. M. Heredity of Coat Color in Mice. Proc. Am. Acad. Art and 

 Set., XI, 1904. 



Castle, W. E. Fifty Years of Darwinism. New York, 1909. 



Castle, W. E. and Allen, G. M. The Heredity of Albinism. Proc. Am. 



Acad. Arts and Sex., XXXVIII, 1903. 

 Cuenot, L. L' Heredity de la Pigmentation ches les Souris. Arch, de Zool. 



Exp. et Gen., 1902, 1903, 1905, 1907. 

 Darbishire, A. D. Note on the Results of Crossing Japanese Waltzing 



Mice with European Albino Races. Biometrika, 1902. 

 Davenport, C. B. Color Inheritance in Mice. Science, XIX, 1904. 

 Durham, F. M. A preliminary Account of the Inheritance of Coat Colors 



in Mice. Reports to the Evolution Committee, IV, 1908. 

 Hagedoorn, A. L. Inheritance of Yellow Color in Rodents. Univ. of Calx 



fornia Publications in Physiology, March, 1909. 

 Morgan, T. H. The Assumed Purity of the Germ Cells in Mendelian Re 



suits. Science, XXII, 1905. 

 . Some Experiments in Heredity in Mice. Science, XXVII, 1908. 



Breeders Association, V, 1909. 

 Riddle, O. Our Knowledge of Melanin Color Formation and its Bearing or 



SOME EXPERIMENTS IX BREEDING SLUGS 

 Certain large naked mollusca or slugs, common in Europe, are 

 noted for their numerous and striking color-variations, some of 

 which seem to be correlated with climatic conditions. Little 

 has been known concerning the inheritance of these color-forms, 

 but Mr. Walter E. Collinge has recently made some experiments 

 in breeding two of the species, Arion ater (or empiricorum) and 

 A. subfuscus. The results of this work are given in the Journal 

 of Conchology, the short paper containing them being Mr. Col- 

 linge 's address as president of the Conchological Society, de- 

 livered October 17, 1908. As the publication is available to 

 few in this country, and the facts cited are very interesting, it 

 seems worth while to abstract part of them. 



Arwn ater is a very large and handsome slug, of which the 

 following color-varieties were used or appeared in the experi- 



(1) ater, pure black. I was not quite clear about the meaning 



