Manchester Memoirs, Vol. xliii. (1899), No. \%. 11 



if it grows on the surface of a humid body or in a liquid 

 where the contained air can be renewed without being 

 displaced by carbonic acid gas, one observes an ordinary 

 mouldiness with a mycelium consisting of more or less 

 slender tubes, branched and interlacing, and producing on 

 the surface of the liquid aerial organs of fructification. 

 Everyone is familiar with such growths of common moulds. 

 But introduce the mould into a sugar solution with in- 

 sufficient air, the growth changes completely, as we have 

 already seen submerged penicilliuin., aspergilhis and 

 mycoderma vini change, only in a more pronounced 

 manner. The spores which are sown for the crop 

 become much enlarged, and the mycelium tubes which 

 proceed from them are much thicker and stronger 

 than in the normal plant. These tubes produce, at 

 relatively greater distances from each other, branch tubes, 

 which detach themselves and set up a separate vegetation 

 on their own account, producing at their extremities, or 

 having their own continuity broken by, chains of large cells 

 which can live by budding and reproduce cells similar to 

 themselves, which also grow into tubes." Does not this 

 description of the change in the growth of a mould — from 

 a delicate moss-like structure to a mere thallophyte — in the 

 absence of free oxygen, with the enlargement and more 

 leathery consistence of the cells, suggest the alleged 

 enlargement and thickening of the characteristic epithelial 

 cells in the cancerous growth? While the higher organisms 

 or organizations of life cannot exist without oxygen, there 

 are lower forms of life which do actually thrive in its 

 absence ; even the larval forms of higher organisms are 

 able to exist under gaseous conditions which would 

 be fatal to the fully developed creatures. It was not 

 without reason that oxygen was called the vital gas ; in 

 its absence the living cells seem to forget their life 



