558 
ADRIAN J. PIETERS 
Table XV 
Series VIII. S. monoica. Mycelium From Media Under Column 2, Transferred to 
0,05 Percent Haemoglobin. Weight of Mycelium in Milligrams after Thirty 
Days' Growth in 200 cc. Liquid. In Numbers 6-17 the Amount of 
Peptone is Always 0.1 Percent, of Sugar 1/50 Molecular, 
and of Salts 1/200 Molecular 
No. 
Food 
f Weight, 
Milligram 
Sporangia 
2 Days 
Oogonia 
ID Days 
Antheridia, 
Percent 
W ight of My 
celium Out of 
Haemoglobin, 
Milligram 
I 
Pea 
.0398 
II 
80 
21 
.0157 
2 
Peptone 0.1% 
.0146 
I 
170 
6 
Lost 
3 
" 0.2% 
.0256 
I 
146 
9 
.0109 
4 
" 0.5% 
.0561 
I-II 
79 
9-5 
.0132 
5 
" 1% 
.0863 
II 
108 
7 
.0138 
6 
" + cucrose . . . 
.015 
II 
62 
6 
.0120 
7 
" -{- maltose . . . 
.0598 
II 
58 
12 
.0144 
8 
" + dextrose. . . 
.0281 
II 
96 
10 
.0128 
9 
" -j- levulose. . . 
.0581 
II 
119 
20 
.0152 
14 
" -j- sucrose 
+ salts 
•3645 
II 
79 
6 
.0191 
15 
" + maltose 
+ salts 
.2151 
o-I 
52 
15 
.0219 
16 
" + dextrose 
+ salts 
.1810 
II 
105 
13 
.0188 
17 
" + levulose. . . 
-j- salts 
.2100 
II 
103 
64 
.0186 
A striking feature of this record is the very large number of oogonia 
found on the mycelium from o.i percent and from 0.2 percent peptone. 
The preliminary tests showed that in this species mycelium from 
0.1 percent peptone produced as many oogonia as that from i percent 
but such a large number as recorded in Table XV was quite unexpected. 
In this series the tests in haemoglobin were conducted in quadruplicate. 
Before making the final records all dishes were carefully examined and 
the number of oogonia in each was found to be practically the same. 
Probably the large number of oogonia is connected with the smaller 
number of sporangia in these lots, for, as has been said, a mycelium 
producing few sporangia is in better condition to produce oogonia 
than one that has produced many sporangia. This fact introduces an 
element of uncertainty into this work that is always present and must 
be taken into consideration in interpreting the results. Leaving 
the record of numbers 2 and 3 out of consideration it is apparent that 
levulose is a food favorable for the formation of oogonia out of pro- 
portion to its value for vegetative growth, and that sucrose with 
0.1 percent peptone alone is probably not available to the plant. 
