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A TEXTBOOK OF THEORETICAL BOTANY 



ascospores, the true nature of which is open to question. Budding takes 

 place very rapidly when the food supply is abundant and is in many species 



%- 





Vacuole 



Nucleus 



Fig. 266. — Saccharomyces cerevisiae. Photograph of 

 cells stained to show nuclei and volutin grains. 



the only known method of multiplication. A bud begins as a small protrusion 

 of the wall of the mother cell, usually near one end, which rapidly enlarges 

 until it is as large as the mother cell itself (Fig. 267). The junction of the 



Fig. 267. — Saccharoviyces cerevisiae. Vegetative 

 cells showing budding. 



two cells is by a very narrow neck, and buds are therefore usually detached 

 easily. Sometimes, however, when growth is most vigorous a bud will itself 

 produce another bud or buds before it is detached, so that a short chain of 

 cells is formed. It is not infrequent to find that the young cells remain 

 attached to each other and to the parent cell for some time, so that quite large 



