MICROSCOPIC OBJECTS. 



Fig. 1. The Yeast-plant (Torula cerevisise or T. sacchari), 

 x 240 diameters. 



This drawing of the Yeast-plant may be taken to represent 

 the typical form of a single cell. The cells increase by the 

 process of budding. In some parts of the figure the cells 

 may be seen in the act of throwing out a bud ; while in others 

 they are united into a perfect chain, which corresponds to a 

 more advanced stage of growth. The manner in which this 

 plant causes the conversion of sugar into alcohol is at present 

 imperfectly understood ; but, from some cause, during the 

 growth of the plant, carbonic acid is thrown off, while alcohol 

 remains in the liquid. 



This plant belongs to the Coniomycetous order of Fungi. 



The cells vary from ^ m to -^^ inch in diameter. They 

 are best examined when mounted in liquid. 



Fig. 2. Maple-blight (Uncinula bicornis), x 90. 



This figure represents the well-known blight or mildew 

 which is found on the leaves of the Maple, chiefly in the 

 months of September, October, and the early part of Novem- 

 ber ; the hedges in the country may sometimes be seen quite 

 white with this blight. The fine fibres in the drawing illus- 

 trate the web of the mildew, and the globular bodies the 

 conceptacles, or cases, in which the eight sporangia are stored 

 for future use; each sporangium contains eight spores. 

 This blight belongs to the As corny cetous order of Fungi. 



The diameter of the conceptacles is from ^ to -^ inch. 



This object may be mounted either in the dry state, in 

 balsam, or in liquid. 



