BOTANICAL: THE LOWER ORDERS. 137 



which such beetles as I have described, on being opened, 

 have been found to be inhabited by a still smaller fungus. 



Nor must we think that we ourselves escape. What 

 is diphtheria, ringworm, what we call "consumption" 

 (phthisis), cancer, and other fatal diseases? Dr. Car- 

 penter tells us, in the work I have mentioned, that a 

 disease of the scalp, in which yellow crusts are formed, 

 consists almost entirely of the mycelium, receptacles, 

 and spores of a fungus, and that the like is true also of 

 those white patches on the lining membrane of the mouth 

 of children which are known as " thrush." 



It will amuse you if I relate a story in which I was 

 the chief actor one of the many singular results of my 

 adventures in lecturing. Some years ago a doctor who 

 attended my family invited me to give one of my 

 lectures to the members of a well-known dispensary 

 now a hospital in my own neighbourhood. I declined, 

 remarking that it was simply presumption; but he 

 pressed so hard that I accepted the invitation. The 

 subject required was to be one that should bring all the 

 members, every one of whom were doctors of medicine 

 or surgeons, together ; so I gave out the subject with a 

 highly attractive title, adding that it was an argument 

 fur the further use of the microscope in disease. Well, 

 the evening came, and I, taking care that I would say 

 nothing I could not prove, armed myself cap-a-pie with 

 diagrams and microscope, and, when all was over, a well- 

 known M.D. said he had an interesting case of death the 

 day before. A child had died of diphtheria, and he 

 thought it a good opportunity to examine the disease 

 with iny instrument ; and, neatly folded up in a napkin, 

 he had brought down some matter for my examination, 

 t.iken from the trachea. 



I wished that I was anywhere but in that lecture- 



