70 MICROSCOPIC FUNGI. 



conclusion^ careful examination was necessary, and 

 new modes of manipulation essential. The details 

 of one method employed were to the following* 

 effect : — A sufficient number of spores were removed 

 on the point of a lancet, and placed on a slide in a 

 drop of alcohol. Before the spirit was quite eva- 

 porated, two or three drops of strong nitric acid 

 were added, and the whole covered with thin glass. 

 The slide was then warmed over a spirit-lamp, the 

 acid not being allowed to boil, but only gradually 

 heated to boiling point. By this means the 

 fruit was found to consist of an outer membrane, 

 nearly transparent, and studded with tubercles;, 

 that this membrane enclosed a number of cells 

 which constituted the apparent joints, and which 

 were natm^ally flattened at either end by mutual 

 pressure, \^^len the outer membrane was dissolved 

 or ruptured, these cells escaped, and became de- 

 tached from each other. The cells, thus set free, 

 exhibited a brownish or yellow ring around a paler 

 area, in the interior of which an inner cell was 

 visible, sometimes globular, often uTegular in shape. 

 The examination of the ring was not entirely satis- 

 factory; it appeared to be sometimes marked with 

 concentric lines having the appearance of wrinkles. 

 The inner cell had granular contents and a central 

 nucleus. '\Anien perfectly free they were spherical 

 in form, with a distinct membrane of their own ; 

 and colourless, except when acted upon by re- 

 agents. The means employed to determine the 



