123 
paper and the conidia allowed to develop to maturity. Conidial length 
here (Graph 64, Fig. O) was somewhat less than under standard conditions 
(see Graph 42, Fig. Kk), and the coefficient of variability was a little high. 
Conidial breadth—H. No. 1 was quite constant in conidial breadth 
as follows: 
M o CV 
6.03 + .04 0.55 +.34 9.13 =.57 
The ratio of conidial length to conidial breadth is an important one 
as determinative of shape. This ratio for H. No. 1 is as follows: 
mean length 22.62 + .05 
mean breadth 6.03 + .04 
= 3.74 + .03 
In a description of H. No. 1, written in May, 1919, for my own use, 
and prepared with considerably more care than is ordinarily used in specific 
descriptions of fungi, I noted the conidia as 3—8 septate and as 52.6—67.2 
*19.2—24 uw long on wheat; and as 48—8418—21.6 w on corn-meal 
agar, whereas my more extended study now shows the mode on wheat as 
78.2 u, the mean as 76.8 uw, and the range from 34 to 98.6 yw; the breadth as 
ranging from 17 to 23.8 uw, with the mean as 20.4 y; the septa with a 
mode of 8, a mean of 7.9, and ranging from 4 to 10. I may here note also 
that Bakke (6) in his description of H. teres gives the conidial dimensions as 
150 [or 105*|—130 x 15—20 », and theseptaas7—14. Thusheseems to have 
found conidia considerably longer than I did, as also narrower ones. It 
should be said that the data obtained by this study of graphs of H. No. 1, 
though involving several thousand measurements, fail to record the longest 
conidium observed, and the one with the most septa, because these were 
both seen during observations which rendered their inclusion impossible; 
which is to say that to include them would have been to consciously 
select these unique conidia for inclusion. Anent the shortcoming of my 
own brief description cited above may be quoted the Saccardian de- 
scription of H. ravenelii: ‘“‘Spongiosum; hyphis flaccidis flexuosis nodosis 
ramosis, inarticulatis; conidiis cymbiformibus, 3-4 septatis, fuscis, 50 
uw longis, endo-chromotibus isthmo connexis.”’ Though the mode is approx- 
imately at 50-54 u the conidia really range from 13 to 71m (see Fig. L). 
Very similar errors, due to brevity of description, exist regarding many 
or all known species. 
*See Pammel, King, and Bakke (90, p. 180). 
