278 
Journal of Agricultural Research 
Vol. II, No. 4 
Tabi,£ I .—Fluctuation of the average sizes of the conidialand perfect stages of Gibberella 
Saubinetii based on the average of 10 measurements —Continued 
Perfect Stage 
Age 
of cul¬ 
ture. 
Pure culture on sterilized— 
Height 
and 
diameter 
of peri¬ 
thecia. 
Potato stem. 
ft 
214 by 183 
225 by 190 
200 by 170 
178 by 130 
245 by 230 
Vicia faba stem.. 
.do. 
Wheat straw. 
Cotton stem. 
Average size and percentage of equiseptate 
ascospores. 
i-septate. 
2-septate. 
£ 
21 by 3-5 
P. ct 
36 
J* 
22 by 3.5 
P.ct. 
13 
15 by 4 
9 
18 by 4 
5 
3-septate. 
Days . 
30.. .. 
30.■ 
60.. .. 
60.. .. 
40.. .. 
22 by 3. 75 
«S by 4 
29 by 4 
18 by 4.25 
24 by 4 
P.ct. 
51 
100 
100 
86 
100 
Plate XIV contains illustrations from Gibberella, the original strain 
from a wheat kernel which failed to germinate. These kernels have a 
carmine color when the subcuticular plectenchyma (PI. XIV, fig. J) is 
well developed. Red is formed as the basic modification of the fungus, 
while yellow is the acid modification, which can be observed on steamed 
rice in pure culture. Fusarium subulatum , F. culmorum , and F. meta- 
chroufn have the same color shades and are also common on cereals, so 
that the red grains are not due alone to the presence of Gibberella. The 
perithecia of this fungus, being blue, as a rule, turn red brown with the 
addition of an alkali. On steamed potato tuber the conidia form a short¬ 
lived pionnotes, which is brownish white to ochreous, depending on the 
moisture and the influence of the carmine, which enters the conidia to 
some extent. The conidia of this pionnotes rapidly swell (PI. XIV, 
fig. H) t separate into cells, germinate, and produce new conidia (PI. XIV, 
fig. X), which anastomose and form a stroma, while in the other species 
mentioned the conidia remain perfect, dry out, and are long-lived. It 
was interesting to note the increase of septa in germinating spores, which 
may have as many as 9 (PI. XIV, fig. H ), while the normal conidia (PI. 
XIV, figs. G and F) have 3 to 5 septa. The ascospores swell (PI. XIV, 
fig. E , 1) like the conidia, and this swelling often lasts even after desicca¬ 
tion. However, cultures on straw may develop a type of ascospores 
with a smooth outline (PI. XIV, fig. E , 2) unless a rapid desiccation 
causes constriction between the septa (PI. XIV, fig. E y 3). A hundred 
asci may be formed in one perithecium, but, as a rule, they are not so 
numerous. Typical paraphyses are seldom seen between the asci, but 
they are present (PI. XIV, fig. D) and are 4 to 6 celled. Perithecia have 
two sizes of cells. Groups of large cells surround the ostiolum like a collar, 
which may or may not be pronounced (PI. XIV, fig. C). Two such col¬ 
lars rarely seen in other perithecia (PI. XIV, fig. A ) proved the fact that 
sometimes two ostioli allow the ascospores to escape. The main body 
of the peridium is small celled, and the arrangement of the cells indicates 
their hyphai origin. A longitudinal section shows the peridium to con¬ 
sist of three layers (PI. XIV, fig. B ). The stroma of Gibberella is very 
