THE CYTOPLASM AND ITS DIFFERENT PRODUCTS 43 



very abundant in the cells about to sporulate, and play, like them, 



the role of reserve material. The results which have been secured 



by Guilliermond l on the evolution of the metachromatics in the 



higher ascomycetes and various molds have confirmed this opinion. 



In the young ascs of the higher ascomycetes, the many metachro- 



matic granules collect about the asco- 



spores in formation when they are 



finally absorbed by the ascospores. In 



the molds (Penicillium, Sterigmato- 



cystis) they accumulate in the fruiting 



heads and serve in the nutrition of 



the conidia. Van Herwerden admits 



that these bodies represent reserve 



products which will be decomposed 



by a nuclease with the formation of 



phosphoric acid, and this favors the 



fermentation. 



According to Amata, 2 two kinds of 



lipoidal granulations may be demon- 



strated in the yeasts by Soudan III. 



Some resist the fat solvents after 



treatment with organic acids and become blackened. The others 



become a brownish color after treatment 

 with organic acids and are dissolved in 

 xylol and ether. The first type is less 

 abundant than the second type. 



B. Glycogen: Glycogen was observed 

 for the first time in yeasts by Errera. 3 It 

 is very abundant in the cells. It is easily 

 reco S nized by the brown color (mahogany) 

 Colored which it gives with iodin in potassium 

 iodide The color disappears when the 



Fig. 48. Yeast cells with a for- 

 mation of mucilaginous network. 

 The network has been obtained 

 by partial drying. 



1, Part of the cells has fallen. In 2 and 

 3 it is seen that the network may affect 

 the form of the entire wall, for example 

 between o and 6; a is a vegetative cell; 

 b an asc with two ascospores; 4 a, three 

 cells living in the network (according 

 to Hansen). 



rk 



Latter have been 

 with Methyl Violet The 

 Network is Uncolored. Some . . 



Cells are still Found in the solution is heated to 60 , but reappears 

 Meshes, but Most of them when it coolg> Glycogen exists in almost 

 are Removed (after Hansen). . 



all of the yeasts; however, certain species 



do not contain it at any moment in their development, perhaps because 

 it is used up as soon as it is formed. In this category, belong S. 

 apiculatus, exiguus, and the Schizosaccharomyces. On the contrary, we 



1 Guilliermond, A. Contr. a Fetude de la formation asques et de l'e"piplasm 

 des Ascomycetes. Rev. ge"n. de Bot. 14, 1903. 



2 Amata, A. Ueber die Lipoide der Blastomyceten. Cent. Bakt. Abt. II, 42, 

 1915. 



3 Errera, L. L'epiplasm des ascomycetes at le glycogene des vegetaux. Thesis 

 d'agregation des sciences, Brussels, 1882. 



