1899] TOXIC EFFECT OF DELETERIOUS AGENTS 301 
spores germinated in the various cultures was noted on two 
occasions, first when from 30 per cent. to 70 per cent. of those 
in the checks had germinated, and again a few hours later. A 
similar method was adopted to indicate the early mycelial devel- 
opment. At some time after germination the germ tubes show- 
ing an average development were measured and noted; this was 
repeated a few hours later, and sometimes a third measurement 
was made. The first appearance of conidia was also noted, but 
a this very frequently occurred at night (between 15 and 22 
hours after inoculation) the point was not so well noted. 
In the earlier work, the cultures in which the spores failed to \ 
seminate were opened at 72 hours and a number of the spores | 
were transferred by means of a sterile platinum needle to a | 
hanging-drop of pure beet infusion in a clean cell, in order to 
test whether they were killed by the agent or merely inhibited. | 
It per cent. or more survived, the culture was classed as 
Wed; if none at all or less than 1 per cent. survived, they’ 
Nae classed as filed. In most of the work, however, the trans- 
fers were made at 48 hours, it being found that all spores that 
aay germinate did so in less than 36 hours and usually much 
The cultures which germinated in the presence of the dele- 
a terious agent were likewise divided into two classes: (1) those 
; Which although they may have been retarded or stimulated in 
4 mycelial development by the agent, finally matured a fair crop 
|) dia in about the norma! time; (2) those, which, although 
, 7 8etminated and continued to grow, presented a markedly 
. ay °F retarded mycelial development, and generally failed 
“ww, Detween these two classes came—as might be sup- 
7 a tumber of cultures which were very difficult to classify. 
a, Cases there would be an apparently normal mycelial 
7 Cince a. but almost total supression of fruiting. In other 
| on "regular, meager, and even yeast-like mycelium would 
Surprise by finally developing a number of apparently 
Cultures ; hours. 
i aa M alcohol, formaldeh H,O KCN were transferred at 72 hours, 
ye : others at 48 hours, e yde, 22a) and Ww 
