INVESTIGATION AS TO ORIGIN OF CATTLE DISEASES. 185 



gTanules wliicli are present in any way cause the disease, tend rather to 

 show that their occurrence shonUl be considered as an effect of the malady, 

 whether constant and inherent, or altogether fortuitous ; for since these 

 granules, if fungous in their nature, must be, as hidicated by the cultiva- 

 tions, forms of the very commonest molds, it is certainly a much more 

 probable hypothesis that the disease so destroys the vitality of a part of 

 the blood as to render it capable of supporting and nourishing a low 

 form of these ubiquitous fungi, which perish when introduced into a 

 healthy subject, than it is to imagine a deadly disease, occurring only 

 under certain rigidly prescribed conditions, as caused by the presence, in 

 the economy of the germs, of fungi notoriously harmless and of universal 

 occurrence. 



It is, of course, possible that these fungi, developed in the fluids of a 

 diseased animal, may become the carriers of contagium. This can only 

 be determined by a series of inoculations upon healthy cattle. 



While the experiments reported above were still in progress, we were 

 fortunate enough to obtain a copy of the Transactions of the New York 

 State Agricultural Society for 1867, containing the " Eeport of the New 

 York State Cattle Commissioners," in connection with the " Special report 

 of the Metropolitan Board of Health on the cattle disease." This report 

 we read with interest. 



The conclusions of Professor Hallier we do not accept, for three reasons : 

 Fkst, because the fluids sent to him were not put up with the proper 

 precautions for exclusion of extraneous spores; second, because the 

 culture apparatus used by him does not give reliable results, as we have 

 found by experiment ; and lastly, because his reasoning is based on a 

 pecidiar theory of his own, that penicillium, mucor, &c., are merely unripe 

 forms of certain ustilagineous fungi, a theory which cannot be discussed 

 here, but of which it is sufficient to say that it has been accepted by no 

 other prominent mycologist. 



The statement of Dr. Stiles, that "the fungous origin of zymotic dis- 

 eases is now conceded by the highest authorities in mycological research," 

 will no doubt surprise the said authorities ; for Berkeley, Curtis, and 

 De Bary, the highest authorities in England, America, and Germany, 

 most assuredly concede nothing of the kind. 



With a culture apparatus, a lenu)n, and a little albuminous fluid, such 

 as blood, serum, white of egg, &c., it is very easy to obtain almost any 

 kind of mold ; but the laws of <levelopment of such organisms are not 

 yet sufficiently known to enable one to draw decisive inferences from the 

 results. 



With regard to the magnifying power necessary for the examination 

 of minute cryptogamic forms, it has usually been overratcnl. A good 

 one-fifth objective is all that is necessary, and in making observations 

 on growing slides is the highest power that can be conveniently used. 

 We have, it is true, used mucli higlier powers, but do not consider them 

 necessary, or even desirable, in microscopic investigations of this char- 

 acter. 



