1914] FROMME—AECIDIUM CUP 33 



metamor 



phosed aecidiospores and aecidiospore initial cells. The central 



ium is formed from 



from 



spore chains. The first peridial cells are produced at the center of 

 the arch and the peridium enlarges from this point centrifugally 

 until the bases of the lateral walls are reached. Its subsequent 

 enlargement is by the basipetal growth and sterilization of the 

 peripheral spore chains. 



Columbia University 



LITERATURE CITED 



1. Arthur, J. C, Auf die Struktur und Entwicklungsgeschichte begriindete 

 Klassifikation der Uredineen. Result. Sci, Congr. Bot. Vienne 1905: 



331-348. 1906. 



2. , Uredinales in North American flora 7: part 2. 1907. 



3- Arthur, J. C, and Kern, F. D., North American species of Peridermium. 

 Bull. Torr. Bot. Club 33:403-438. 1906. 



4- DeBary, A., Comparative morphology of the fungi (English translation). 

 London. 1887. 



5. Blackman, V. H., Fertilization, alternation of generations, and general 

 cytology of the Uredineae. Ann. Botany 18:323-373. 1904. 



6. Blackman, V. H., and Fraser, Miss H. C. I., Further studies on the 

 sexuality of the Uredineae. Ann. Botany 20:35-48. 1906. 



7- Christman, A. H., Sexual reproduction in the rusts. Bot. Gaz. 39:267- 



2 75- 1905. 

 8. , The nature and development of the primary uredospore. Trans. 



Wis. Acad. Sci. 15:517-526. 1907. 



9- -, Alternation of generations and morphology of the spore forms in 



the rusts. Bot. Gaz. 44:81-101. 1907. 



10. Dittschlag, E., Zur Kenntnis der Kernverhaltnisse von Puccinia Fal- 

 cariae. Centralbl. Bakt. 28:473-492. 1910. 



11. Fisher, E., Uredineen der Schweitz. Bern. 1904. 



12. Fromme, F. D., Sexual fusions and spore development of the flax rust. 

 Bull. Torr. Bot. Club 39:113-131. 191 2. 



13. Grove, W. B., Evolution of the higher Uredineae. New Phytol. 12:89- 

 105. 1913. 



14. Harper, R. A., Nuclear phenomena of sexual reproduction in fungi. 

 Amer. Nat. 44:533-546. 1910. 



15. Hoffman-, A. W. H., Zur Entwicklungsgeschichte von Endophyllum 



Sempervivi. Centralbl. Bakt. 32:137-158. 191 2. 



