266 
Journal of Agricultural Research 
Vol. I, No. 3 
14 to 17 days.—Discharge of spores from the pycnidia increasing. 
21 to 25 days.—Exudates from the pycnidia increasing and uniting. 
40 days.—Pycnidia abundant, forming a black crust over the surface of the medium. 
Exudate of spores from the pycnidia a yellowish slimy mass. 
67 days.—A few long cylindrical bodies present. Hyphae mostly hyaline. No 
chlamydosporelike bodies. 
Rice, with the exception of com meal, is the best of all the media tried. Spores 
are formed abundantly and exuded in large droplets from the pycnidia. A very scant 
mycelial growth is formed on rice. 
Bouillon (5725 J ) 
3 days.—No visible growth. 
6 days.—A very sparse flaky white growth arising from individual spores lodged 
against the glass below the surface of the medium. 
8 days.—Growth below the surface of the medium from individual spores enlarging 
and adhering to the glass. No floating hyphae. Slight surface growth against 
the glass. 
10 days.—Increase in mycelial growth. 
14 days.—Pycnidia forming a black ring against the glass at the surface of the medium. 
29 days.—Pycnospores very few, poorly developed, and not typical of the spores on 
com meal or rice. 
56 days.—Hyphse'hyaline, with many intercellular, spherical swellings singly or in 
chains. 
Beef Agar (5726*) 
3 days.—Grayish, thick, felty growth, extending % cm. above surface of medium; 
irregular in outline. 
6 days.—Growth spreading; white pycnidia forming, 
8-10 days.—Pycnidia forming a black line on the surface of the medium at the 
point of contact with the glass; elsewhere on the surface of medium they are 
collected into spots. 
14 days.—Pycnidia large and black and increasing in number. 
29 days.—No pycnidia at the edge of mycelial growth except in contact with glass. 
Spores few and imperfectly formed. 
56 days.—Hyphas hyaline, with many intercellularly or terminal spherical bodies 
several times the diameter of the hyphse arranged singly or in chains. Very 
few typical spores. 
These results of tests with the different media 1 2 bring out clearly 
the fact that the development of the foot-rot organism is decidedly good 
on some media and very poor on others. Numerous pycnidia and an 
1 This medium was prepared in the Laboratory of Plant Pathology. 
2 In addition to the results of growth obtained on the nine media discussed in the preceding pages, the 
fungus was cultivated on a number of others, but not for the purpose of comparing the growth at the end 
of stated periods of time; hence, these have not been included in the general description. Growth of the 
fungus has been studied on mature stems of cotton (Gossypium herbaceum ), sweet clover ( Melilotus clba), 
also on immature stems of sweet clover, lupine ( Lupinus sp.; common varieties from Germany), oak (Quer- 
cus sp.), tomato ( Lycopersicon esculenium) , and sweet potato ( Ipomoea batatas). The growth and produo 
tion of fruiting bodies varied greatly on the different media. On oak and cotton there was but a sparse 
growth, although a few pycnidia were formed. On tomato there was practically no growth. Numerous 
fruiting bodies were produced on stems of sweet clover (mature and immature), sweet potato, and a fair 
growth of hyphae with production of pycnidia on lupine. Mycelium is so sparingly formed that when 
produced abundantly it is a sign that the medium is not suited to the best development of the fungus. 
The production of pycnidia, on the other hand, is evidence that the medium is a most favorable one. 
