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plasm within, and it is continuous throughout. So long as 

 this form of growth goes on the hyphse are submerged in the 

 fluid, or only floating near the surface ; but after a time, in 

 accordance with some change in the conditions of the fluid, 

 one hypha will send up a vertical branch, which grows so as 

 to stick up out of the water ; and the aerial processes so 

 formed are most difficult to wet, for they have the power of 

 throwing off" the Avater on account of the adherence of air to 

 their surfaces. This vertical branch grows up and sends out 

 three or more processes, which become constricted and broken 

 up into little balls (fig. 3 a). All this takes place simply by 

 prolongation ; there are no cells in this matter ; there may be 

 partitions in the protoplasm, but there are no nuclei and no 

 subdivision of such bodies. Each of the spherical bodies at 

 the end of the aerial stalk at which we have arrived is a 

 spore or conidium such as we started from, and one would 

 think that this was a complete life-cycle. There is, however, 

 a singular variety of other and secondary developments. 



One of the commonest — I found them in all cases where I 

 got the mycelium just described — I will now mention. When 

 a conidium is developing and sending out its first hypha, it 

 will frequently send out from the other side a moniliforni 

 process which breaks off* and floats about (fig. 4). Sometimes 

 each globule in these detached masses seems to have a 

 nucleus. This (fig. 4 a) is the Torula form ; it is the same 

 as yeast, differing only in size in this particular case. If the 



conditions are favorable, absolutely the whole development 

 of the spores or conidia may be Torulse. The great condition 

 which favours this is the absence of atmospheric air. It is 

 an ascertained fact that this Torula form grows without 

 oxygen and without light : this is a physiological fact of the 

 highest importance, established by Pasteur, with regard to 

 Penicillium-yeast. What is the fate of Torula? what is its 

 further development ? Some of these floating masses become 

 very mycelium-like (fig. 5), similar in appearance to what 

 has been called Cladospora. I have never found mycelium 



