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BRIEFER AR PIC UES. 
THE ORGANS OF ATTACHMENT IN BOTRYTIS VULGARIS. 
(WITH PLATE XVII) 
WuiLE engaged during the present year with a series of cultures of 
the common greenhouse fungus familiarly known as Botrytis vulgaris, 
the attention of the writer was attracted by the facility with which 
conidiophores and organs of attachment mutually replace each other 
as the result of changes of external conditions. The interest of such 
facts from a theoretical standpoint makes it seem worth while to record 
the following observations which were conducted under the direction 
of Professor V. M. Spalding. 
Preliminary artificial cultures were prepared, each in a drop of malt 
solution on a glass slide. The first two, although as nearly alike as 
possible, showed very different results. One in the course of three 
days was completely covered with conidiophores (fg. 7), while in the 
other these were almost entirely absent, a development of peculiar 
cellular masses, the so-called organs of attachment, having taken place 
instead (fig. 6). The phenomenon suggested at once a relation of 
Some kind between the organs of attachment and the conidiophores. 
Other cultures were then prepared on slides, both plane and with 
concave centers, in test tubes, flasks, Petri dishes, etc., with the result 
that whenever the hyphe came in contact with the hard surface of the 
culture dishes, these peculiar bodies appeared, and whenever the 
yphe grew upward without contact, conidiophores developed. 
In order to determine with certainty whether or not the formation 
of conidiophores and organs of attachment could be controlled at will, 
the following cultures were prepared: Ina drop of malt solution, 
Placed on each of several slides with concave centers, were sown one or 
mere conidia, and over the drop was suspended, by means of strips of 
ra blotting paper, a coverslip (2x1). These cultures were then 
transferred to moist chambers until wanted. The slips were placed at 
taneus heights, if close to the drop (1-2 above) in twoor three days the 
cheat. overhanging surface was covered by organs of attachment, while 
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