340 Osborn. — Spongospora subterranea , ( Wollroth ) Johnson. 
Bibliography. 
Bloomfield, J., and Schwartz, E. J. (’10) : Some Observations on the Tumours of Veronica 
Chamaedrys caused by Sorosphaera Veronicae. Annals of Botany, vol. xxiv, p. 35. 
Dobell, C. Clifford (’09) : Chromidia and the Binuclearity Hypothesis. Q. J. Micros. Science, 
vol. liii, N. S., p. 279. 
Harper, R. A. (’00) : Cell and Nuclear Division in Fuligo varians. Botanical Gazette, vol. xxx, 
p. 217. 
Hartmann, M. (’09) : Autogamie bei Protisten. Archiv f. Protistenkunde, vol. xiv, p. 264. 
Jahn, E. (’04) : Myxomycetenstudien, III. Kernteilung und Geisselbildung bei den Schwarmern 
von Stemonitis flaccida. Ber. der deutsch. bot. Gesell., vol. xxii, p. 84. 
(’07) : Myxomycetenstudien, VI. Kernverschmelzungen und Reduktionsteilungen. Ibid., 
vol. xxv, p. 23. 
— (’08): Myxomycetenstudien, VII. Ceratiofnyxa. Ibid., vol. xxvi#, p. 342. 
Johnson, T. (’08) : Spongospora solani (Brunch.). Economic Proc. Roy. Dublin Soc., vol. i, p. 453. 
(’09) : Further Observations on Powdery Potato Scab, Spongospora subterranea. Sci. 
Proc. Roy. Dublin Soc., vol. xii, N. S., p. 165. 
Kranzlin, Helene (’07) : Zur Entwicklungsgeschichte der Sporangien bei den Trichien und 
Arcyrien. Archiv f. Protistenkunde, vol. ix, p. 170. 
Lister, A. (’93) : On the Division of the Nuclei in the Mycetozoa. Journal Linn. Soc. Botany, 
vol. xxix, p. 529. 
Lotsy, J. P. (’07) : Vortrage fiber botanische Stammesgeschichte, vol. i, Algen und Pilze, p. 391. 
Maire, R., and Tison, H. (’09) : La cytologie des Plasmodiophoracees, &c. Annales Mycologici, 
vol. vii, p. 226. 
Massee, G. (’08) : Corky Scab of Potatoes. Journ. Board of Agric., vol. xv, p. 592. 
Nawaschin, S. (’99) : Beobachtungen fiber den feineren Bau und Umwandlungen von Plasmodio- 
phora Brassicae. Flora, vol. Ixxxvi, p. 404. 
Olive, E. W. (’07) : Evidences of Sexual Reproduction in the Slime Moulds. Science, N.S., 
voh xxv, p. 266. 
■ (’07) : Cytological Studies on Ca-aiiomyxa. Trans. Wisconsin Academy of Arts, 
Science, and Literature, vol. xv, pt. ii, p. 753. 
Pavillard, J. (TO) : Etat actuel de la Protistologie v^g^tale. Progressus Rei Bot., vol. iii, p. 474. 
Prowazek, S. (’05) : tlber den Erreger der Kohlhernie Plasmodiophora Brassicae , Woronin. 
Arbeiten aus dem kaiserlichen Gesundheitsamte, vol. xxii, p. 396. 
Read, T. (TO) : The Anatomy of some Tubers. Annals of Botany, vol. xxiv, p. 537. 
Schwartz, E. J. (TO) : Parasitic Root Diseases of the Juncaceae. Annals of Botany, vol. xxiv, 
p. 511. 
EXPLANATION OF PLATE XXVII. 
Illustrating Mr. Osborn’s paper on Spongospora. 
All figures were drawn in outline with a Zeiss camera lucida at the table level, with a tube 
length 160 mm. Except where stated, a Zeiss 3 mm. apochromatic oil-immersion objective (1-30 
aperture) was used with (Figs. 1-15 inclusive) a x 6 compensating ocular and (Fig. 17 ad. fin.) 
with a x 18 comps, occ. The magnification was thus roughly 900 and 2,750 diameters respectively. 
Fig. 1. Single uninucleate amoeba in young host cell. 
Fig. 2. Three amoebae in a cell, one binucleate; note the young starch grains which are also 
present. 
