As long ago as 1853, Dr. Lauder Lindsay examined and reported on cholera evacuations, and in 1856 he declared--"It will be evident that I can see no satisfactory groundwork for the fungus theory of cholera, which I am not a little surprised to find still possesses powerful advocates."[I] And of the examinations undertaken by him he writes:--"The mycelium and sporules of various species of fungi, constituting various forms of vegetable mould, were found in the scum of the vomit, as well as of the stools, but only at some stage of decomposition. They are found, however, under similar circumstances, in the vomit and stools of other diseases, and, indeed, in all decomposing animal fluids, and they are therefore far from peculiar to cholera."
Some writers have held that the atmosphere is often highly charged with fungi spores, others have denied the presence of organic bodies to any extent in the air. The experiments conducted in India by Dr. Cunningham[J] have been convincing enough on this point. This report states that spores and similar cells were of constant occurrence, and were generally present in considerable numbers. That the majority of the cells were living and ready to undergo development on meeting with suitable conditions was very manifest, as in those cases in which preparations were retained under observation for any length of time, germination rapidly took place in many of the cells; indeed, many spores already germinating were deposited on the slides. In few instances did any development take place beyond the formation of mycelium or masses of toruloid cells, but in one or two distinct sporules were developed on the filaments arising from some of the larger septate spores, and in a few others _Penicillium_ and _Aspergillus_ produced their characteristic heads of fructification.
With regard to the precise nature of the spores and other cells present in various instances little can be said, as, unless their development were to be carefully followed out through all its stages, it is impossible to refer them to their correct species or even genera. The greater number of them are apparently referable to the old orders of fungi--_Sphæronemei_, _Melanconei_, _Torulacei_, _Dematiei_, and _Mucedines_, while some probably belonged to the _Pucciniei_ and _Coæmacei_. Amongst those belonging to the _Torulacei_, the most interesting was a representative of the rare genus _Tetraploa_. Distinct green algoid cells occurred in some specimens. Then follow in the report details of observations made on the rise and fall of diseases, of which diarrhoea, dysentery, cholera, ague, and dengue were selected and compared with the increase or diminution of atmospheric cells. The conclusions arrived at are:--