412 MYCODEKMA. 



Mycoderma cells, and is easily distinguished from that occurring 

 in the case of typical, oval yeast cells. 



If a pastorianous Mycoderma cell be sown in a nutrient 

 solution e.g., wort or grape- juice and its development be 

 followed under the microscope, it will be found to bud at one end 

 in exactly the same manner as true yeast (see Fig. 193 a). As 

 soon as the daughter cell (2) is completely formed, it buds (b) in 

 the direction of its longitudinal axis, whilst the parent cell throws 

 out a new daughter cell (3) at one side of the place whence the 

 first cell (2) made its appearance. These new daughter cells in 



turn bud longi- 

 tudinally (c), 

 whilst their 

 parent cells again 

 develop lateral 

 buds (d). Even- 

 tually the assem- 

 blage of buds 

 a, b c d, assumes a form 



FIG. 193. Aggregation of buds from Mycoderma. Cells similar to tnat f 



2, 5 and 7 are surrounded by an envelope of air. & pine-tree, the 



Magn. 600. central stem and 



lateral branches 



of which continue to grow in their initial direction, whilst 

 branching out regularly every year. In the case of Myco- 

 derma cells, this branching occurs about every two hours in a 

 good nutrient solution; and as, when grown in wort or grape- 

 juice, the assemblage of buds is not broken up by ascending 

 bubbles of carbon dioxide, it frequently consists of hundreds of 

 cells. 



When a nutrient gelatin is employed as substratum, in which 

 the cells are compelled to develop in situ, the cells commence to 

 bud in the same manner ; but since the daughter cells are unable 

 to spread out uniformly, as is the case in or upon a liquid, a 

 compact, spherical colony is formed, like those of beer or wine 

 yeasts. 



With regard to the giant colonies (see p. 393, vol. ii.), LINDNER 

 (XXXI.) rightly calls attention to the fact that their variability of 

 form is greater in this case than with any other group of budding 

 fungi. According to that worker, " In some cases the colonies form 

 a dull grey to yellowish grey mass without any surface markings, 

 or else veined, like leaves ; in others a number of delicate and 

 closely set concentric rings are exhibited, or wedge-shaped strata 

 proceed from the centre of the colony, spreading out and usually 

 assuming a dry, mealy appearance, or the entire surface becomes 

 covered with innumerable fine or coarse wrinkles. In still other 

 cases the colony takes the form of a hill, with a number of 

 circular walls thrown up on the slopes ; or it resembles a 



