142 



ORIGIN OF THE YEASTS 



These anastomoses prove then, that, although sexuality may have 

 disappeared, there seems to be a rudimentary sexual attraction quite 

 comparable to the phenomena which have been observed in certain 



yeasts (Schw. occidenta- 

 lis, yeasts of Rose and 

 Dombrowski, etc.). 

 However when one 

 compares these anas- 

 tomoses with the sexual 

 production of Eremas- 

 cus fertilis, he is struck 

 by the resemblance 

 which exists between 

 the method of forma- 



tion of 



ascs in these 



Fig. 57. A. Showing Copulation and Asc Formation two fungi (Fig. 57). 

 in Eremascus fertilis; B, The Same for Endomyces In one and the other, 



f two contiguous cells 



produce protuberances which seem to search for each other. With 

 Eremascus fertilis, they reunite 

 to form an egg while in E. 

 fibuliger they constantly fail in 

 their attempt. (Fig. 57, A 

 and B.) It is not doubtful that 

 the anastomosis which precedes 

 the formation of the asc in the 

 latter fungus represents traces 

 of an ancestral reproduction 

 analogous to that which occurs 

 in Eremascus fertilis to which 

 E. fibuliger is closely related. 

 We may then regard E. fibuliger 

 as a form derived from a genus 

 neighboring Eremascus fertilis. 

 The ascospores have the same 

 form as those of Willia anomala; 

 they are hemispherical and pro- 

 vided with a projecting color 

 giving them the appearance of 

 a hat. On the other hand, 

 they are supplied, like those of E. fertilis, with two membranes. The 

 external membrane is burst during germination. The ascospores ger- 

 minate either in the form of yeasts or with a mycelium. 



Fig. 58. Endomyces capsularis. 



1, Fragment of the Mycelium Showing the Formation 

 of Yeasts. 2 and 3, Fragment of the mycelium Pro- 

 ducing Ascs. 



