81 



Having examined these bodies in alcohol alone with more 

 care, I had no doubt that they were the true spores removed 

 from their attachment by the action of washing. I have 

 yet to see these spores in situ. 



The slides I present to the cabinet of the Section will 

 show that the diseased hairs are covered by nucleated cells, 

 square, attached end to end, and branching in all directions. 

 This is the mycelium, or what I hold to be the true parasitic 

 plant. It possesses the same relation to the spore that a 

 tree does to its seed, and, if we keep this in view, the life- 

 histor}^ in the main of most, if not all, these plants becomes 

 easily understood. The full and complete life-history, which 

 must include of necessity the mode in which reproduction 

 takes place in plants so minute as these, requiring Jin. object 

 glass even to see them, will probably long remain unwritten, 

 but analogy leads us to expect that at some period of the 

 life of these plants, and in some way or other, a true sexual 

 process of reproduction does take place. 



There is no doubt that the spores, which you will see on 

 the slides presented, give existence to the mycelium, and 

 then this again produces filaments bearing the spores. These 

 filaments must not be confounded with the mycelium. The 

 cells of these filaments having very different characters. 

 Infection or contagion (one or both) will then take place 

 whenever the spores find a resting place upon the skin of 

 animals in that condition of health suited for their develop- 

 ment. In the cases that came immediately under my notice 

 the worst occurred where bodily health was impaired, 

 whereas contagion did not take place in one instance, even 

 though the boy slept regularly with his brother for months 

 during the continuance of the disease. 



I was quite unable to obtain mycelium from the shin of 

 the face in the case of the adult. The disease travelled all 

 over. the face, leaving the beard and whiskers unattacked; 

 but although the hair folicle of the upper lip was filled with 

 mycelium, I could not get it from the skin. 



