492 ANDREWS: PROTOPLASMIC STREAMING IN Mucor 
cutting an actively streaming part in two streaming ceased and did 
not recommence. 
My experiments as regards injury have been performed on both 
Mucor stolonifer and M. Mucedo, and in both plants I obtained 
the same results. Schroter used Mucor stolonifer and Phycomyces 
nitens. I can confirm his results on M. stolonifer, but I was not 
successful in preserving P. nitens for this study. 
When the filaments of actively growing specimens had their 
tips removed, a temporary increase in streaming was observed, 
due to the outflow of some of the contents and a relief of the pres- 
sure. This streaming could be traced back for a considerable 
distance among the filaments of the injured specimen. The 
streaming caused by such injury soon ceased. The specimens 
were then put away for 24 hours under favorable conditions and 
afterwards observed. They were found not to have been killed 
and were still in a living and streaming condition. 
By separating the filaments of the fungi into two parts the 
specimens were not killed. They were observed after 18 hours 
and were found, Schréter states,* to have healed the wound. All 
of them were living, and streaming was either directly observable 
or was produced by the addition of a sugar solution. 
A light pressure on the cover glass is sufficient to stop streaming 
temporarily and this, as Schréter states, will recommence when 
the pressure is relieved. The time of recovery of the streaming 
will depend on the amount of injury imparted and varies from an 
immediate recommencement to one delayed a few seconds. eh 
sure is, however carefully applied, too severe to excite streaming 
in these fungi or to accelerate that which may be present. A 
momentary acceleration may seem in some cases to be produced, 
but this is simply due to a partial compression of the filaments. 
When thisis relieved the streaming will continue as before. 
INFLUENCE OF LIGHT 
It has been known for a long time, as mentioned by ao 
that light may cause streaming. Also Ewart} makes referen 
* Schriter, loc. cit. 17. 
+ Pfeffer, W. Plant physiology 3: 318. 1905. 
t Ewart, loc. cit. 71. 
