696 
Journal of Agricultural Research 
Vol. XXIII, No. 9 
agar plate, and on sterile sand. On April 23 one sclerotium was developing conidia; 
on May 10 conidia were developing from most of the sclerotia; and on May 26, a sclero¬ 
tium on the agar was developing an apothecium. 
Thus, under sterile conditions, the apothecial stage was produced from 
field-borne sclerotia. 
Experiment VIII.—April 15. A large number of sclerotia from the field, mostly 
from Dr. Howell's place at Orlando, Fla., were placed on moist sand in half-liter 
Erlenmeyer flasks and subjected to a variety of conditions. 
May 8. Flask No. 1, placed at once in a moist chamber in the laboratory, showed 
apothecial stalks arising from two or three sclerotia. Flask 2, which had been placed 
out of doors under the east side of the building, where it was subject to a little sunlight 
early in the morning, and during the day to ordinary daylight conditions, with a 
temperature fluctuating from rather cool at night (approximately io° C.) to rather 
warm in the day (approximately 27°) showed several small apothecial stalks arising. 
Flask 4, after having been held in the ice box for a week, then subjected to room con¬ 
ditions, showed dozens of stalks, none of them as yet mature. 
May 12. Flask No. 1 showed many well-formed apothecia. No. 2 showed more than 
a dozen short stalks with well-formed cups nearly mature. No. 4 showed many well- 
formed cups. On May 22 these were photographed within the flask (PI. 11, B), 
and then removed still attached to the sclerotia and photographed in a Petri dish. 
(10, PI. XL). Some of these were then dried in the sun, and others were preserved 
in alcohol. 
May. 24. Flask No. 3, which had been held thus far in the dark under conditions 
as favorable as any of the others as regards moisture, and in a constant warm tempera¬ 
ture, without a sign of the development of apothecia, was placed out of doors under 
the east side of the house. Almost immediately apothecial development began to 
occur. On June 2, eight days later, several apothecia as well formed as in No. 2 had 
arisen. 
This experiment, together with the repeated observation that had been 
made that apothecial stalks were distinctly phototropic, indicated that 
light is one of the essential factors for the production of apothecia from 
sclerotia. It also indicated that the use of moist sand in Erlenmeyer 
flasks was a convenient and favorable method for keeping moisture con¬ 
ditions right. Thereafter this method was used extensively for the pro¬ 
duction of apothecia. 
Experiment IX.—May 28, 1919. A large number of field sclerotia were collected 
and planted upon moist sand on a glass plate placed upon the laboratory table, the 
whole being covered with a bell jar. On June 3, six days later, apothecial stalks are 
already arising. 
The development being so much quicker in this case than ever before 
indicates a marked seasonal influence. Whether this consists of simply 
more favorable temperature or of a difference in light duration or of 
some other factor is not known. 
A still later placing of sclerotia, these under absolutely pure culture 
conditions, the sclerotia having been derived from pure cultures and 
having been placed on sterile sand, was examined on September 17. 
Apothecia were produced in abundance from sclerotia of strains Bi, 
B 21, B 35, and B 37, the two latter having been authentic single coni- 
dium strains. 
Experiment X.—About the middle of March field sclerotia were collected and sub¬ 
jected to outdoor conditions in a variety of locations in an attempt to produce apothecia 
under more nearly natural conditions. The first lot of sclerotia was placed on sand in a 
shallow wooden box, which was subjected to moist conditions by placing on a thick 
bed of “ Spanish moss'’ (Tillandsia sp.) kept saturated with water, and covering the 
whole witn a large moist chamber built of window sash. On April 21 it was noted that 
this was becoming very hot during the middle of the day, and since apothecia had not 
yet been produced, the box of sand was removed and placed in the shade of some 
boxes on the west side of the house and kept moist by waterings from time to time. 
Chi April 24 under these more favorable conditions, temperature apparently being a 
factor, apothecial stalks began to form, and on May 3 mature apothecia were collected. 
