— 218 — 



In nature we may expect to find elementary species with 

 still other chromosome numbers and the existence of those diffe- 

 rent chromosome-sets gives a further insight in the cause of the 

 huge variety. 



The future problem of chromosome investigation is an experi- 

 mental inquiry in the behaviour and significance of chromosomes, 

 and by those investigations it is necessary to work on the prin- 

 ciple of pure lines. Viola tricolor and other Melanium-sipecies 

 give good promises for this kind of experiments, and I hope 

 in the following years to be able to continue the work com- 

 menced. 



The microscopic investigations have been carried out in the 

 Botanical Laboratory at the University of Copenhagen. I owe 

 Professor Raunkiær my best thanks for the interest, which he 

 has shown in my investigations and am very much indebted for 

 the many excellent suggestions, which he has made to me. I ex- 

 press my sincere gratitude to Mr. Henning E. Petersen, Dr. 

 phil. Lecturer, for the helpful suggestions he has given me during 

 the microscopic investigation. 



Literature. 



W.Becker (1904): Systematische Behandlung der Viola arvensis s. 1. auf 

 Grundlage unserer phylogenetischen Kenntnisse. — Mitteilungen des 

 thüring. bot. Vereins. Neue Folge. Heft 19. 



— (1910): Violae Europaeae. — Dresden. 



H. Federley (1913): Das Verhalten der Chromosomen bei der Spermato- 

 genese der Schmetterlinge Pygaera anachoreta, curtula und pigra sowie 

 einige ihrer Bastarde. — Zeitschr. für ind. Abstamm. und Vererb. lehre 

 Bd. 9. 



■ — (1915): Chromosomenstudien an Mischlingen I, II and III. — - Öfversikt 

 af finska Vetenskaps-Soc. Förhandlingar. (a) : Bd. 57, No. 26; (b) : Bd. 

 57, No. 30; (c): Bd. 58, No. 12. 

 M. Ishikawa (1916): A list of the number of chromosomes. — Bot. Magaz. 

 Tokyo. Bd. 30. 



W.Johannsen (1913): Elemente der exakten Erblichkeitslehre. — ■ Jena. 



Karl B. Kristof ferson (1914): Ueber Bastarde zwischen elementaren Spe- 

 cies der Viola tricolor und V. arvensis. Vorläufige Mitteilung. — Bo- 

 taniska Notiser 1914. 



— (1916): Om nedärvning av herkogami och autogami hos Viola. — ■ Bo- 

 taniska Notiser 1916. 



