522 Schwartz.—Parasitic Root Diseases of the Juncaceae. 
Bibliography. 
1. Woronin (’ 78 ) : Plasmodiophora Brassicae. Jahrb. f. wiss. Bot., xi. 
2 . Goebel (’ 84 ): Tetramyxaparasitica. Flora, lxxii, p. 517. 
3 . Weber (’ 84 ) : Wurzelanschwellungen von Juncus bufonius. Bot. Zeit. 
4 . Schroter (’ 89 ): Engler and Prantl’s Die Natiirlichen Pflanzenfamilien, Lieferung 36 . 
5 . Dangeard (’ 91 ) : Sexual Reproduction of P'ungi. Le Botaniste, No. 3. 
6. Wisselingh (’ 98 ) : Pringsheim’s Jahrb., p. 637. 
7 . Nawaschin (’ 99 ) : Plasmodiophora Brassicae. Flora, lxxxvi. Band. 
8. Prowazek (’ 05 ) : Plasmodiophora Brassicae. Arbeiten aus dem kaiserlichen Gesundheitsamte, 
vol. xxii, Berlin. 
9 . Maire and Tison (’ 09 ) : Cytologie des Plasmodiophoracees. Annales Mycologici. 
10 . Blomfield and Schwartz (’ 10 ) : Sorosphaera Veronicae. Annals of Botany, January, 1910. 
EXPLANATION OF PLATE XL. 
Illustrating the Paper by Mr. Schwartz on Root Diseases of the Juncaceae. 
The drawings were made with the aid of the Camera Lucida. 
Fig. 1. Portion of tangential section of a root, showing the early stage of the disease. X 512. 
Fig. 2. An amoeba with its nuclei in the ‘cruciform ’ stage of their division, x 1100. 
Fig 3. An amoeba with its nuclei in the ‘ dumb-bell ’ stage of division, x 1100. 
Fig. 4, a-h. Various stages of nuclear division. See Text for description. 
Fig. 5. Portion of a root-hair infected by the Sorosphaera. x 730. 
Fig. 6. Infected cortical cell. X 73 °- 
Fig. 7. Enlarged drawing of ‘ cruciform ’ stage of nuclear division. 
Fig. 8. Amoeba showing schizogony, x 730. 
Fig. 9. Dumb-bell stage of nuclear division, x 730. 
Fig. 10. Root-hair with infection by a six-nucleate amoeba. x 730. 
Fig. 11. Root-hair infection, x 730. 
Fig. 12. Cortical cell filled with spores, x 730. 
Fig. 13. Portion of root-hair with spores, x 730. 
Fig. 14. Portion of outer cortex of root showing the disease in its reproductive stage, x 730. 
Fig. 15. A sorosphere. x 730. 
Fig. 16. Surface view of a portion of a sorosphere. x 1180. 
P'ig. 17. Nuclear division being completed in amoebulae prior to spore formation. x 730. 
Fig. 18. Chromidial or akaryote stage. x 1100. 
Fig. 19. Formation of fresh nuclei in the vacuoles, x 1100. 
Fig. 20. A sorosphere. x 730. 
Fig. 21. First mitosis of newly-formed nuclei, x 730. 
Fig. 22. Second mitosis of newly-formed nuclei. x 730. 
Fig. 23. Amoebulae forming into spores, x 730. 
Figs. 24 and 25. Root-tubercles of J. articulatus . Natural size. 
Fig. 26. Ripe spore of Entorhiza. x 730. 
Fig. 27. Conidial infection of root-hair by Entorhiza Junci. x 730. 
Fig. 28. Young binucleate spore, x 730. 
Fig. 29. Formation of young spore at end of twisted hypha. x 730. 
Fig. 30. Portion of section of root-tubercle of J. articulatus. x 325. 
