26 Professor Marshall Ward [Feb. 24, 



of animal maladies due to fungi proper are known. Whether this is 

 due to the more acid nature of vegetable sap, to the high temperature 

 of animal tissues, or to the greater abundance of the anti-bodies in 

 animals, cannot be decided. 



The lecturer gave illustrations of caterpillars with their destroyers, 

 Cordyceps, Isaria, etc., growing from their mummified bodies, and 

 referred to Torrubia's " Vegetable Wasp" legend of 1749. He also 

 showed photographs of the " plant- worms " used in Chinese medicine, 

 and rapidly surveyed the work of Cesati, Pasteur, De Bary, Cohn, 

 etc., on Muscardine, Entomophthora, Empusa, Saprolegnia, and other 

 insect-killing fungi. 



But these entomophagous fungi are merely particular cases of 

 mycoses. Every group of animals from the Protozoa and Infusoria 

 upwards have their fungus parasites ; hyphas penetrate the ceratin of 

 sponges and the calcareous walls of corals, and fishes and amphibia 

 are by no means immune. 



Birds and mammals suffer particularly from certain mycoses due 

 to fungi which we have been in the habit of regarding as harmless 

 moulds, e.g. Aspergillus, and even man is sometimes in danger from 

 such fungi. 



When, in 1869-70, Grohe and Block showed that small doses of 

 the spores of Penicillium and Aspergillus are fatal to kittens, their 

 statements were emphatically disbelieved ; but Grawitz confirmed 

 them, and the body of evidence showing that Aspergillus contains 

 poisons toxic to birds and higher animals can no longer be overlooked. 

 Some of these forms of aspergillosis are very serious diseases indeed. 



While the new era of mycology was stimulating observers to new 

 investigations into the life-histories of moulds, and of the parasites 

 of animals and plants, and into the setiology of the timber-destroying 

 fungi, and so forth, on the one hand, it was, on the other, gradually 

 attracting to its domain areas of investigation which had grown up 

 independently out of the past, and which the older thinkers could 

 never have dreamed of associating with fungi. 



A conspicuous example was the study of fermentation, which, 

 since Janssen in 1590 had brought forward a microscope of several 

 lenses, and Leeuwenhoek had applied an improved form of it to the 

 animalculae in putrefying liquids, had undergone the initial stage of 

 passage into the hands of the naturalists. 



The lecturer then sketched in rapid outline the history of the 

 theory of fermentation, from the early days when the lees or sediment 

 (yeast) were known as the " Faeces Vim " — apparently owing to the 

 shrewd suggestion of a Venetian doctor, who, in 1762, said putre- 

 factive and fermentation processes are due to the vital acti\'ity of 

 minute worms, the excreta {faeces) of which induce the turbidity and 

 mal-odour of the liquid — to the days when the living plant-nature 

 of these "/«eces" was gradually estabUshed by the work of Astier, 

 1813, Desmazieres, 1826, Quivenne, 1838, and Persoon, and especially 



