BACTERIA ON THE SURFACE OF PLANTS. 



35 



was alkaline. In case of fungus growths the reaction was acid. The constant occurrence of 

 the bacteria or of the fungi in the interior of the water calyx in no way injures the host 

 plant. The author ascribes the presence of bacteria or 

 fungi to alkaline or acid secretions of the plant, but 

 inasmuch as he seems to have determined the reaction 

 only after the organisms had grown in the fluid, his con- 

 clusion does not necessarily follow. 



These organisms are really still outside of the plant. 

 Their presence here, while extremely interesting, is only 

 to be compared with what occurs in the mouth-secretions 

 of animals, and it is doubtful if there is any true sym- 

 biosis, i. c, mutual profit. 



The most recent reference to this subject, so far as 

 known to the writer, occurs in an address by M. C. 

 Potter (Trans. British Myc. Soc, 1910, Vol. Ill, p. no) 

 from which fig. 5 is borrowed. He found numerous 

 bacteria on the surface of leaves (potato, artichoke, etc.), 

 and cultivated them therefrom by making impressions of the leaves on gelatin plates. 



LITERATURE. 



1890. 



1893- 



1896. 



1897- 



1 90 1. 



1902. 



Treub. M. Les bourgeons floraux du Spatho- 

 dea campanulata Beauv. Annates du Jardin 

 Botanique de Buitenzorg, vol. VIII, 1890, pp. 

 38 to 46, 3 plates. 



Wiesner, Julius. Ueber ombrophile und 

 ombrophobe Pflanzenorgane. Sitzungsb. K. 

 Ak. d. Wissenschaften, Math. Naturw. Classe. 

 Wien., 1893, Bd. 102. Abt. I, pp. 503-521. 

 See also Wiesner: Pflanzenphysiologisehe 

 Mittheilung aus Buitenzorg (in). Ueber den 

 vorherrschend ombrophilen charakter des 

 Laubes der Tropengewaehse. Ibid., 1894, 

 Bd., 103, pp. 169-191. 



Hoffmann, F. Untersuchungen iiber die 

 Grosse der Mikroorganisraenzahl auf Getreide- 

 kornern unter verschiedene Bedingungen. 

 Wochenschrift fur Brauerei, Jg. xin, 1896, 

 No. 44. [Not seen.] 



Koorders, S. H. Ueber die Bliithenknospen 

 Hydathoden einiger Tropischen Pflanzen, pp. 

 354 to 477, 8. Das eonstante Vorkommen 

 von BacterienodervonFadenpilzenimlnneren 

 der Wasserkelche. Annates du Jardin Bo- 

 tanique de Buitenzorg, 1897, vol. xiv, pp. 

 451 to 452. 



WurTZ, R. et BourgEs, H. Sur la presence 

 de microbes pathogenes a la surface des 

 feuilles et des tiges des vegetaux qui se sont 

 developpes dans un sol arrose avec de l'eau 

 contenant les micro-organismes. Arch, de 

 Med. Experim. et d'Anat. Pathol., Paris, 

 1901, Ser. 1 to 13, pp. 575 to 579. 



Papasotiriu, J. Untersuchungen iiber das 

 Vorkommen des Bakterium coli in Teig, Mehl 

 und Getreide, nebst einigen Bemerkungen 

 iiber die Bedeutung des Bakterium coli als 

 Indikator fur Verunreinigung von Wasser mit 

 Fakalien. Archiv fur Hygiene, 41 Bd., Miin- 

 chen and Berlin, 1902. Verlag von R. Olden- 

 bourg, pp. 204-210. 



1902. Chrzaszcz, T. Die Mikroorganismen der 

 Gersten und Malzkorner. Wochenschrift f. 

 Brauerei, Jg. xix, 1902, No. 40. [Not seen.] 



1903 Burri, R. Die Bakterien vegetation auf der 

 Oberflache normal entwickelter Pflanzen. 

 Centralb. f. Bakt, 2 Abt., x Bd., pp. 756 

 to 763. 



1904. Duggeli, Max. Die Bakterien flora gesunder 



Samen und daraus gezogener Keimpflanzchen. 

 Centralblat f. Bakt., Jena, 1904. n Abt., 

 Band xn, pp. 602 to 614, and 695 to 712, 

 1904, Band xin, pp. 56 to 63 and 198 to 207. 



1905. Metcalf, H. Organisms on the surface of 



grain, with special reference to Bacillus coli. 

 Science, N. S., vol. xxn, No. 562, 1905, pp. 

 439-441. Also a separate. 



1905. Smith, Erastus G. Note on the occurrence 



on grain of organisms resembling the Bacillus 

 coli communis. Science, N. S., vol. xxi, 1905, 

 pp. 710 to 711 



1906. Prescott, Samuel C, with cooperation of 



Erastus G. Smith, William J. Mixter and 

 Selskar M. Gunn. The occurrence of organ- 

 isms of sanitary significance on grains. Biolo- 

 gical Studies by the Pupils of William Thomp- 

 son Sedgwick, Boston, June, 1906, pp. 208-222. 



1907. Barber, Marshall A. On heredity in certain 



micro-organisms. Kansas University Science 

 Bull., March, 1907, vol. iv, No. 1 (whole 

 series, vol. xiv, No. 1), pp. 3 to 48, plates 

 1 to iv, and 3 text figs. 

 1910 Potter, M. C. Bacteria in their relation to 

 plant pathology. The British Mycological 

 Society, Transactions for the Season 1909, 

 vol. in, part 3, published May 2, 1910. 1 

 plate, pp. 150-168. See also Centralb. f. 

 Bakt , 2 Abt., xxvm Bd., pp. 624-640. 



*Fig. 5. Impression of leaf of Heliantkus tuberosus on gelatin after 3 days' incubation. The form of the leaf is 

 outlined by the development of numerous bacterial colonies, germs of which were present on the surface of the leaf. 



