86 
toplasm of the cells, stimulated into increased activity by parasitic gem- 
mules. While there is but little doubt that Plasmodiophora brassiere, 
Wor., is the principal cause of club-root, it is by no means improbable 
that bacterial forms play quite an important part. Pure cultures should 
be made of the various forms so generally present and inoculation ex¬ 
periments tried. 
J hereby desire to acknowledge with sincere thanks the assistance 
I have received through the kindness of Prof. Spaulding, under whom 
the work was begun and has been carried thus far. I am indebted to 
Dr. Erwin F. Smith of the Division of Yegetable Pathology of the 
TJ. S. Department of Agriculture, to Dr. Byron D. Halsted of the Yew 
Jersey Experiment Station, and to Mr. George A. Schultz, of Jaines- 
burg, Y. J., who kindly furnished me with material. To the botanists 
of the various experiment stations and other correspondents, whose 
suggestions have been of much value, I am also under obligations. 
University of Michigan, February 14, 1891. 
Botanical Laboratory. 
BIBLIOGRAPHY. 
The list appended is not at all complete, but comprises all the works 
consulted. Many I have not seen in the original, brief abstracts alone 
being available. 
1. Adam. Agriculture, vol. n, p. 51. London, 1789. 
2. American Agriculturist. January, 1867; August, 1868; August, 1869. 
3. Atkinson, George F. Preliminary Report on Root Gall. Science contributions 
Agr. Exp. Sta., Auburn, Ala., December, 1889. 
4. Beijerinck, M. W. Die Papilionaceenknollchen. Bot. Zeit., 1888; Rev. in Bot. 
Cbl., Bd. 38, 1889, p. 458. 
5. Bird, James. Disease in Turnips. Trans. High. Agr. Soc., 1857-’59, p. 307. 
6. Brunckorst. fiber die Knollclien an den leguminosen Wurzeln. Ber. d. Dent. 
Bot. Ges., Bd. in, 1885, p. 241; Abst. Bot. Cbl., Bd. xxiv, 1885, p. 333. 
7. Buckman, James. Finger-and-Toe in Root Crops. Jour. Roy. Agr. Soc., 1853-’54, 
p. 125. 
8. Country Gentleman’s Magazine, vol. i, 1868, p, 40. 
9. Curtis. Insects affecting the Turnip Crop. Jour. Roy. Agr. Soc., 1841, p. 193. 
10. Dickson’s Agriculture. London, 1807. 
11. Donaldson’s British Agriculture, 1838, p. 556. 
12. Duncan, James. Report on Cause of Finger-and-Toes. Trans. High. Agr. Soc., 
1859-’61, p. 197. 
13. Farquharson. Communication Respecting Diseases in Turnips. Trans. Highland 
Agr. Society, 1830. 
14. Heinzelmann, F. Die Ivolilkrankheiten. Scliweizer. Landw. Zeitschr, 1882, pp. 
526-530. 
15. Henderson, P. Club-root in Cabbages. Country Gentleman. Albany, N. Y., 
1879, p. 807. 
16. Hulst. Club-root. Bull. Agr. Exp. Sta., N. J., Dec., 1888. 
17. Hunter, W. B. Finger-and-Toe in Turnips. Trans. Highland Agr. Soc., 1855-’57, 
p. 347. 
18. Kuhn, Jul. Wurzelfeinde des Kohls. Deutsche Landwfrthsck. Ztg., Bd. xxi, 
1878, No. 85. 
