POLYMORPHISM OF MICROBES. 277 
tion, as Cocardas states that he has seen them, united 
and borne by a single hypha, magnified 225 diameters. 
Each form of Penicilliwm belongs to a special 
change in the syrup. In syrup which has become 
turbid, the ferment is in the corpuscular or bac- 
teridian stage; when the syrup is ropy, it is in the 
zooglairian or filamentous stage; when it has turned 
sour, it is in the stage of aquatic fructification ; 
finally, when the syrup is mouldy, it is in the stage 
of aérial fructification. 
Cocardas states that he has observed this really 
astonishing polymorphism while making tse of the 
ordinary precautions for averting gross errors. Not- 
withstanding facts of the same kind, which have been 
put forward previously, notably by Hallier, but which 
are frequently contradicted by more accurate research, 
it may be asked whether this is not merely a pheno- 
menon of confusion, analogous to that which was 
rightly or wrongly supposed to exist in the case of 
lichens. Fresh researches, made with greater pre- 
cision in sterilized liquids, and accompanied by the 
most scrupulous precautions, are necessary before 
these facts can be definitively accepted by science. 
Polymorphism of Fungi of the Human Skin.—It 
is more easy to accept, at any rate in part, the poly- 
morphism recently noted by Grawitz in the fungus 
of Favus (ringworm), which we have already de- 
scribed under the name of Achorion Schoenlenii, 
Grawitz asserts that Achorion Schoelenii of ring- 
