11 



appeared. Probably the endocarp has been in some way altered 

 through tbc (ligestion, but if this alteration is of pliysical or of 

 chemical nature is undecided, He reters sbortly to the papers by 

 Alfred Fischer (ö) and William Crocker (2) published in 1907; 

 these Iwo authors dilTer much in the explanation of the causes 

 which abohsh the delayed germination of the seeds of many water 

 plants, and at present we must confess, that the whole queslion is 

 open. It is to be hoped that further experiments soon may settle it. 



LITTERATUR. 



1. Birger, Selim: Uber endozoische Samenverbreitung durch Vögel. — 



Svensk Botan. Tidskrift, I, 1, 1907, pp. 1—31. 



2. Crocker, William; Germination of Seeds of Water Plants. — Botan. 



Gazette, 44, 1907, i)p. 375—380. 



3. Darwin, Charles: Om Arternas Oprindelse. Dansk Oversa'ttelse, 



1872, p. 451. 



4. Ekstam, Otto: Einige bliitenbiologische Beobachtungen auf Spitzbergen, 



— Tromsö Museums Aarshcfter, 20, 1898, pp. 51—54. 



5. Fischer, Alfred: Wasserstofl- und Hydroxylionen als Keimungsreize. 



— Ber. deutschen bot. Gesellsch., 25, 1907, pp. 108—122. 



6. Hesselman, Henrik: Några iakttagelser öfvcr växternas spridning. — 



Botan. Notiser, 1897, pp. 101—108. 



7. HoLMROE, Jens: Notizen iiber die endozoische Samenverbreitung der 



Vögel. — Nyt Magaz. f Naturvidensk., Kristiania, 38, 1900, pp. 303 

 —320. 



8. Kerner von Marilaun, A.: I^ilanzenleben. Bd. 2, 1891, pp. 799 — 800. 



9. Ostenfeld, c. H.: l^hytogeographical Studies etc. — Botany of the 



Fseröes, I, Copenhagen 1901, pp. 116—117. 



10. Ostenfeld, C. H.: Om Vegetationen i og ved Gudenaaen nan' Ban- 



ders. — liotanisk Tidsskrift, Köbenhavn, 26, 1905, p. 390. 



11. RosTRUP, OvE: Aarsberelning fra Dansk I^rökontrol for 1899 — 1900. 



Köbenhavn, 1900, pp. 33 — 35. 



12. Sernander, R.: Den skandinaviska vegetationens spridningsbiologi. 



Upsala, 1901. 



13. Sernander, R.: -Entwurf einer Monographie der europäischen Myrme- 



kochoren. — K. Svenska Vetensk. Äkad. Handl., 41, N:o 7. 1906. 



14. Sauvageau, C: Notes biologiques sur les Potamogeton. — Journal 



de Botanique, VIII, 1904, p. 166. 



