488 ANDREWS: PROTOPLASMIC STREAMING IN Mucor 
On two occasions, as will be observed by referring to TABLE Iv, the 
streaming stopped once for 4 and at another time for 8 seconds to 
the sugar and to the water, respectively, and in starting did so with 
a jerk. After the 3 hours of experimentation with the fungal 
filaments in the above mentioned manner the specimen was put 
away for 24 hours at the optimum temperature to see if this 
treatment had had any detrimental effect. It was again observed 
at the end of this time and found to be in a perfect condition, and 
it again responded to the reagents which produced streaming as 
readily as when the experiment was at first begun. This experi- 
ment is similar to the one performed by Schréter* with a sugar 
solution and water, which I have also repeated and can confirm. 
The streaming may also be caused to recommence when it has 
been stopped by cold. Specimens of Mucor Mucedo, M. stolonifer, 
and Phycomyces nitens grown in 10 per cent gelatin ceased to 
show streaming when suddenly transferred from a temperature 
of 24° to 9° C. When a 5 per cent solution of cane sugar was 
added, streaming began again in 15 seconds, but as is to be ex- 
pected, not so rapidly as in specimens that were kept at optimum 
temperatures. The same specimens were then subjected to a 
temperature of 5° C. after washing out the sugar with water; and 
in this case too streaming was induced by a 5 per cent solution 
of cane sugar, but a longer time was required. The streaming was 
feeble and was not seen until one minute after the sugar Was 
applied. The direction of motion was to the sugar solution, which 
was applied first to one end and then the other with previous 
washing with water before each new application. It is not neces 
sary to use as high a concentration of sugar (10 per cent) as 
mentioned by Schréter.t A higher concentration of sugat than 
5 per cent will start streaming in less time and more rapidly than 
mentioned above. No matter what concentration of sugat solu- 
tion was used, the protoplasm did not flow as freely or as rapidly 
as when the plants were growing under the most favorable circum 
stances. The most favorable results are obtained if the sug 
solution is applied immediately after streaming has been stopped 
by cold. ee 
* Schriter, loc. cit. 21, 22. 
+ Schroter, loc. cit. 21. 
