6 
mucous membranes of affected horses, and by the other fluids 
of the body, the abundance of moisture, and the high and 
equal temperature, all lessen the tendency to secrete a thick 
cuticle; and the whole vital power is thrown instead into 
reproduction. Micrococcus and sporoids are formed in large 
quantities, and both will reproduce the fungi spores in a 
comparatively short time. 
Among various observations, I would refer to the fact that 
one cultivation of micrococcus resulted in a penicillium, and 
another produced Tilletia spores. The particulars of the 
development in these cases, and the general results of the 
cultivation, I would prefer to reserve until a fuller account 
can be presented. 
The presence of these spores* in all the discharges, as well 
as on the mucous membranes, and even in all the fluids of 
the body, the blood, urine, etc., so far as investigated, revives 
another question. It has often been asked, whether such or- 
ganic growths are the consequence of the diseases which they 
accompany, or their cause. Mycologists, naturally, and many 
medical gentlemen, incline to the latter belief’ A large num- 
ber of physicians, on the other hand, many of them of very 
high standing, take the opposite view. 
In the case of the potato disease, in Europe, it has been 
conclusively proved that it is caused by the spores of the 
Peronospora infestans ; and for the grape disease, that it is 
caused by an Hrisyphe. 
I mention these few instances, out of many, to show that in 
cases of diseases or of epidemics among plants, it has been 
proved that they are caused by the growth of certain fungi. 
The same holds good for a large number of epidemics on an- 
imals of the lower orders. As examples, the pernicious in- 
fluence of the micrococcus of Ascophora elegans, on bees; of 
Fumago salicina, on the worms of the pine-spinner, and of 
Empusa on flies, may be mentioned. 
It appears, then, that for the lower orders of organisms 
where the material is abundant and can be gathered withou 
too much expense, the theory has been provel; for the 
higher orders of animals, where the material is expensive, the 
acceptance of the theory is refused. 
It is certainly a singular coincidence that in the case, for 
instance, of the Texan cattle disease, so ably investigated by 
Professors Stiles and Harris, a micrococcus was found in large 
quantities, which produced a singular fungus, the Philolobus. 
* Though the term ‘‘spores” is not strictly correct, it may serve for the 
time best to convey the idea. 
