410 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1914. 
It is fortunate that they are so well suited for thesis problems of \ 
graduate students, and we may hope that the traditions established 
in the laboratories of Farlow and Atkinson may be perpetuated as 
well in other institutions. 
IV.—THE CULTURE PROBLEMS. 
While De Bary in Germany was laying the foundation of myco- 
logical morphology, Pasteur in France was doing a correspondingly 
important work on the side of physiology, dealing with the funda- 
mentals of fermentation and nutrition. Following his initial efforts, 
the problem of the pure culture with yeasts and bacteria was promptly 
defined and solved. Bacteriology not only came quickly into exist- 
ence, but soon became the most exact science of the biological group, 
owing to the fact that in such pure cultures environmental conditions 
can be controlled to a degree unattainable with the higher organisms. 
Brefeld’s success in culturing the smuts directed attention to this 
new method in studying the fungous parasites. Although the meth- 
ods were adapted from those of the bacteriologists their uses with 
fungi are somwehat different. With these it is not only the gain 
from exact handling in differentiating mixed infections and mocu- 
lating from pure cultures, but also in completing life-history investi- 
gations. With the imperfect fungi and Pyrenomycetes the method 
is especially applicable and the recent work on Glomerella by Shear ! 
and Edgerton? illustrates well its advantages. To this method 
Phytophthora infestans has at last yielded the clue to its complete 
life history,’ although here as always the developments in the culture 
tube need to be checked by comparison with those in nature. 
For culturing the plant pathogens the value of the solid over 
liquid media and of vegetable over animal extracts becomes increas- 
ingly evident with experience. Thus the merits of Clinton’s oat agar 
which gave such important results with Phytophthora have again 
been shown by the development upon this medium in our laboratory 
of perithecia of the apple scab fungus in greater abundance and vigor 
than ever observed in nature.‘ It should be assumed that for all 
such fungi which develop part of their fruiting stages saprophytically 
we may perfect culture media and methods which will not only stimu- 
late but may improve on those of nature. 
1 Shear, C. L. and Wood, A. K., Studies of fungous parasites belonging to the genus Glomerella. U.S. 
Dept. Agr., Bu. Pl. Ind. Bul. 252. 1913. 
2 Edgerton, C. W., Plus and minus strains in an Ascomycete. Science, N. 8. 35: 151. 1912; also paper 
read at this Atlanta meeting. 
3See Jones, L. R. and Giddings, N. J. Studies of the potato fungus. Science, N. S. 39: 271. 1909. 
See also ibid. 30: 813. 1909; 31: 752.1910. Clinton, G. P., Oospores of potato blight. Science, N. 8. 33: 744. 
1911; Conn. Agr. Exp. Sta. Rept. 1909-10: 753. Jones, Giddings and Lutman, Investigations of the potato 
fungus. U. S. Department Agriculture, Bu. Pl. Ind. Bul. 245. 1912. Pethybridge, G. H., On pure 
cultures of Phytophthora infestans De Bary and the development of oospores. Sci. Proc. Royal Dublin 
Soc. 13: 556. 1913. 
4See abstract of paper by F. R. Jones: “‘Perithecia in cultures of Venturia inaequalis.’”’? Phytopa- 
thology 4: 52. 1914. 
