STUDIES ON FERMENTATION. 137 



and mycoderma tini when submerged, but with this difference, 

 that in the case of the mucor the changes in question, and the 

 activity of nutrition under these new conditions, are much more 

 marked than in the case of those other organisms. The spores 

 grow larger and the filaments of mycelium which do develop 

 are much stronger than those in the normal plant. These fila- 

 ments put forth, here and there, other filaments which detach 

 themselves and vegetate at the side of the others, being ter- 

 minated or interrupted by chains of large cells, species of 

 spores which can live by budding and reproducing cells similar 

 to themselves or by elongating into filaments. 



Plate V. represents the living plant submerged at a little 

 depth, and having, consequently, still at its disposal a certain 

 quantity of air, insufficient, however, to supply the oxygen 

 needed for all the acts of nutrition. In this case the mucor 

 appears very difierent, morphologically, from what it is when 

 in free contact with air. Here it forms short filaments, having 

 a diameter double or triple that of the filaments of the ordi- 

 nary mycelium with branches and buds all over, and what is 

 especially characteristic, forming a network of chains of cells, 

 sometimes spherical, sometimes oval or pear-shaped, which are 

 the actual spores. These, as soon as they are detached, bud in 

 their turn, and reproduce either cells or branching tubes ; these 

 cells or the chaplets which they form being known under the 

 name mycelian spores or conidia. Our plate gives these different 

 aspects very correctly, and affords us a good idea of the 

 luxuriant state of this remarkable vegetation. 



Plate YI. represents the plant living at a greater depth with 

 less air, expending, by means of sugar as source of heat, the 

 energy which it acquired in vegetating under the influence of 

 the oxygen of the air. The filaments are fewer and older in 

 aspect, and the number of cellular forms is proportionately 

 larger than in the former case, the budding giving rise by 

 preference to spherical or oval cells. On a single cell we often 

 see two, three, four, five, six, and even more buds. 



