MacDougal : Symbiosis and Saprophytism 529 



the higher plant as the organism of the leguminous tubercle, is not 

 capable of general application. Such relation has been proven be- 

 tween Podocarpus and the peronosporous fungus of its mycorhiza 

 only. 



VII. Two types of endotropic mycorhizas may be distin- 

 guished ; one adapted for nitrogen fixation, and a second for the 

 absorption and modification — perhaps oxidation — of the soil prod- 

 ucts before liberation in the tissues of the higher plant. The ex- 

 tension of information will doubtless result in the further division 

 of the second type. 



Literature to which Referenxe is made. 



1. Bonnier and Mangin : Recherches sur la respiration des tissues 

 sans chlorophyll. Ann. Sc. Nat. VI. i8 : 203. 1884. 



2. Engler u. Prantl : Die naturl. Pflanzenf., 2 : 11. . 



3. Pf effer : Pflanzenphysiol. i : 349. 1897. 



4. Heller : New plants from western North America. Bull. Torr. 

 Bot. Club, 25 : No. 4. April, 1898. 



5. Janse : Les endophytes radicants de quelques plantes javanaises. 

 Ann. d. Jard. d. Buitenzorg. 14: 53. 1896. 



6. Jennings and Hanna : Corallorhiza innata R. Br. and its my- 

 corhiza. Sc. Proc. Roy. Soc. Dublin, N. S. 9: [pages?]. 1899. 



7. Johow : Die chlorophyllfreiHe Humusbewohner West Indiens, 

 biologisch-morphologisch dargestellt. Pringsh. Jahrb. f. wiss. Bot. 16 : 

 445. 1885. 



8. Lory : Sur la respiration et la structure des Orobanches, et 

 autres plantes vasculaires deporvues de partes vertes. Ann. Sc. Nat. 

 III. 8: 158. 1847. 



9. Lundstrom : Einige Beobachtung ueber Calypso borealis. Bot. 

 Centralb. 38: 697. 1889. 



10. MacDougal: Symbiosis and Saprophytism. Am. Nat. 33: 

 210. 1899. 



11. MacDougal: Symbiotic saprophytism. Ann. Bot. I : i. 1899. 



1 2 . Nobbe u. Hiltner : Die endotropische Mycorhiza von Podo- 

 carpus, und ihre physiologische Bedeutung. Landw. Versuchssta. 51 : 

 241. 1898. 



13. Reichenbach : Orchidiographische Beitrage. Linnaea, 41 : 53. 

 1877. 



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