ZOOLOGY AND BOTANY, MICEOSCOPY, ETC. 497 



Trichophyton remained sterile in cultivations attempted with a solution 

 of phosphate of soda and tartrate of ammonia, with Cohn's fluid, 

 milk, carrot infusion, turnip infusion, salt solution (0 • 75 per cent.), 

 egg albumen, egg albumen and potash, and vitreous humour and 

 potash. The only method by which it was grown was by moistening 

 the hairs with vitreous humour. When moistened with vitreous 

 humour, the spores on the sides of the hairs placed in cells were seen 

 to grow into a mycelium, and free growth took place when the hairs 

 were floated on the surface of this fluid in test-tubes. It did not grow 

 in cells when the hairs were immersed in a large drop, nor in test- 

 tubes when the hairs were kept at the bottom of the tube. 



The growth observed consisted in a formation of mycelium, which 

 sprouted from the spores in the hairs, and in the formation of spores 

 in the newly-formed mycelium. 



It was shown by experiments in which Aspergillus, Penicilliiim 

 glaucum and other fungi grew around the hairs, whilst the spores of 

 Trichophyton remained sterile, that the latter is essentially distinct 

 from the common fungi whose spores are present in the atmosphere. 



The fact that the spores of the Trichophyton will not grow when 

 immersed in vitreous humour, whilst they do grow when only moistened 

 by it, explains why inflammatory exudation from the blood-vessels 

 cures ringworm of the scalp. 



Absorption of Pigment by Bacteria.*— Dr. Thin, in reference to 

 the fact that certain fungi possess the property of taking up colouring 

 matter from the medium in which they grow, has observed in the 

 Trichophyton tonsurans that both in man and in the horse the fungus 

 may acquire a dark colour from absorbed jDigment. In the case of 

 the horse, he found the mycelial wall represented by an apparently 

 empty dark tube, and at the same time spores blackened with a coating 

 of pigment. 



An analogous appearance exists in bacteria. 



The bacteria found in the cultivations referred to in the preceding 

 note are seen in the transition forms of a spore or coccus, an elon- 

 gating spore, rods, elongated rods, sometimes of great length, long 

 rods, with the first appearance of a diiferentiation of the protoplasm 

 into sporules, and finally as tubes full of spores or cocci. 



These appearances have been followed in several specific 

 organisms, and first of all in Bacillus anthracis. They would seem to 

 indicate the ordinary life-history of at least many bacteria. Fre- 

 quently the preparations contained long bacteria rods which had taken 

 up pigment from the hair. This pigment was often found at one end 

 of a long rod, whilst towards the other end the rod was free from it, 

 and in the part of the rod in which the pigment was found the spore 

 formation could in several instances be seen to be more advanced than 

 at the part which was free from pigment. The pigment was packed 

 in the tubes around and between the spores, but, by focussing, it could 

 be seen that the substance of the spore was free from it. The free 

 spores and short rods were free from pigment. The bacteria in which 



* Proc. Royal Soc, xxxi. (1881) pp. 503-4. 



