HOBSON : MOLLUSCA AND GENETIC RESEARCH. 231 



Literature. 



1. Baltzer, F., Arch. f. Zellforsch., Bd. xi, Hft. 2, 1913, p. 151. 



2. Bateson, W., Problems of Genetics, London, 1913. 



3. Boycott, A., Journ. Conchology, vol. xiv, 1913, p. 100. 



4. Cockerell, T. D., American Naturalist, vol. xliii, 1909, p. 510. 



5. COLLINGE, W., Journ. Conchology, vol. xii, 1909, p. 235. 



6. CoLTON, H., Proc. Ac. N. Sci. Philadelphia, vol. Ixviii, 1916, p. 440. 

 6a. COUTAGNE, G., Ann. Soc. Agric. Lyon, ser. Vll, torn, ii, 1894, p. 397. 



7. Crampton, H., Carnegie Inst. Washington, No. 228, 1916. 



8. Dendy, a., British Association Eeports, Portsmouth, 1911 (1912). 



9. GULICK, J. T., Carnegie Inst. Washington, No. 25, 1905. 



10. Kleiner, E., Zeitschr. Ind. Abst. v. Vererb., Bd. ix, Hft. 3, 1913, p. 216. 



11. KxJNKEL, E., Verb. Ges. D. Naturf. Leipzig, No. 83, 1912, p. 437. 



12. Lang, A., Festschr. z. Geburtstage, E. Haeckel, Jena, 1904, p. 439. 



13. Lang, A., Zeitschr. Ind. Abst. v. Vererb., Bd. viii, Hft. 3, 1912, p. 254. 



14. Mayer, A., Mem. Mus. Comp. Zool., t. xxvi, 1902, p. 117. 



15. Pelseneer, Mem. in 8vo Ac. Eoy. Belgique, ser. il, t. v, 1920, p. 658. 



16. Stelfox, a., Journ. Conchology, vol. xiv, 1915, p. 293, 



17. Stelfox, A., Journ. Conchology, vol. xv, 1918, p. 268. 



18. Weldon, W., Biometrika, vol. i, 1901, p. 109. 



19. Weldon, W., Biometrika, vol. iii, 1903, p. 299. 



