A. E. Lechmerd. 
3*2 
The general routine of any culture is as follows:—After inocu¬ 
lation, a mycelium is formed and grows rapidly, forming a fringe 
around the medium. Sporocysts are formed after thirty-six hours, 
and continue to be formed till the third or fourth day in increasing 
proportions; after the fourth day resting sporocysts or gemmae are 
formed, and by the ninth day the mycelium is found to be thickly 
covered with these and all growth seems to have stopped. In this 
condition the mycelium can remain for an indefinite period. On 
transferring some of the mycelium bearing resting sporocysts and 
gemmae to a fresh medium, these germinate in the manner already 
described and so the life-cycle can be repeated. 
Sporocysts seem only able to be formed as long as the medium 
in which the mycelium is growing is fresh ; as soon as it has 
been in the same medium for a few days, the formation of sporo¬ 
cysts is inhibited, yet if the mycelium is transferred to another 
Petri dish with the same medium, but in which there has been no 
previous growth, the formation of sporocysts continues for a further 
period of about three days, and then stops again. 
One other phenomenon is frequently exhibited in cultures 
where numerous zoospores are present, and apparently comes 
into play at the close of the second motile stage. This is 
“ adelphotaxy,” or the mutual attraction of zoospores at close 
quarters The zoospores are very numerous in these cultures, and are 
necessarily brought into close contact while swarming in a small 
drop of water. As their motions become less active, the attraction 
they exhibit for one another becomes more marked, and they are 
frequently found collected together into a mass, in which state they 
germinate and form the new mycelium (Fig. 29). 
Summary. 
As the result of keeping a species of Saprolegnia under obser¬ 
vation for a period of five months, it has been found possible to 
obtain on the same mycelium the methods of asexual reproduction 
which are characteristic of six different genera, viz:— Saprolegnia , 
Achlya, Leptomitus, Pythiopsis, Dictyuchus and Aplanes. 
It is believed that, although previous observers have thrown 
doubt on the validity of this classification as a result of their 
observations on the sporocysts of different genera, this is the first 
time that the characters of so many genera have been obtained from 
one species. 
