ANDREWS: PROTOPLASMIC STREAMING IN MUCOR 465 
Schréter also used several of the media I have just mentioned, 
but they differ in some respects as to the various ingredients and 
concentrations. I did not have good success in my experiments 
with citric acid on the fungi studied and abandoned it entirely 
after a few experiments. With the exception of the water and 
citric acid solutions I obtained good growths of large actively 
streaming fungi. The protoplasm sometimes moved as rapidly 
as from 2 to 4 mm. per minute, and it often maintained this move- 
ment to and from the apex for hours under the artificial conditions 
to be mentioned later, or as long as the observation lasted, which 
was frequently continued from morning till evening and recom- 
menced the following day. : 
Some specimens of Mucor stolonifer and M. Mucedo were kept 
growing in a weak solution of grape juice and still others in a 
dilute solution of plum juice for five days. The streaming was 
apparent during all this time whenever the plants were placed 
under artificial conditions. In this culture medium the hyphae 
were small and the growth weak. They were grown in a hanging 
drop solution of the substances above referred to on a cover glass, 
and this was cemented to a glass ring cell by means of the wax 
mixture previously mentioned. The glass ring cell was cemented 
to the slide with soft paraffin. <A better growth than in the last 
case, and also a specimen that lived longer, was produced by the 
Spores of Mucor Mucedo in a 1 per cent solution of cane sugar. In 
this mixture most of the spores germinated, forming long hyphae. 
Many of these spores germinated very unevenly although all were 
mature. Some of them began to germinate only after two or three 
days or even longer, after others sown at the same time had pro- 
duced hyphae of considerable length. The specimens were ob- 
Served from time to time, and the movement of the protoplasm 
Could be seen although not so rapid or in such volume as in those 
Specimens grown in some of the nutrient media mentioned earlier 
in this paper. This protoplasmic movement was often evident 
almost as soon as germination was well begun and continued 
generally, when artificial conditions were introduced, for the entire 
life of the filaments. The growth shown by this experiment was 
not very rapid and the fungal filaments were small. Klebs* also 
*Klebs, G. Bedingungen der Fortpflanzung bei einigen Algen und Pilze 
506, 597. 1896, 
