CH. Ill] FUNGI. 71 



deep glass ring is placed on a broad glass slide and a 

 drop of previously sterilised olive oil allowed to run in, or 

 melted paraffin may be run in, in the same way while the 

 slide and ring are hot ; this cements the ring to the slide, 

 while a cover-slip placed on the ring like a roof supports 

 the hanging drop. Or a chamber may be made as 

 described and figured by Marshall Ward, loc. cit. p. 131, 

 which is especially useful where it is desired to control the 

 nature of the atmosphere to which the drop is exposed. 



Everything being sterilised and the cell ready, take a 

 clean cover-slip, heat it between two sheets of talc over a 

 flame, and allow it to cool. Then, with forceps, place the 

 cover-slip on any convenient support, and with a platinum 

 needle place a drop on the centre. The drop is got 

 thus : 



Infect a tube (gelatine or fluid medium) with a drop of 

 water containing spores, and shake thoroughly. Hold a 

 platinum needle in a flame, and let it cool ; dip it into the 

 infected medium and place the drop on the cover-slip. 

 Then rapidly invert the latter, and cement it to the cell 

 with gelatine, or with oil, or paraffin. 



The drop should contain one spore, and trials have to 

 be made to insure this. In gelatine media, the student 

 can work with two to five spores if well isolated. 



All the foregoing experiments can be repeated with 

 drop-cultures. 



(84) Germination. 



Place a culture containing one spore in focus under the 

 microscope. Record the temperature, and fix the spore 



