CHAPTER III. — SPORES OF FUNGI. 



77 



are the commencements of spores ; they are formed simultaneously and soon become 

 invested with firm membranes, and grow as they lie arranged in a longitudinal row 

 inside the ascus to about double their original size. The protoplasm which surrounds 

 them at first disappears rapidly in Peziza pitya as they increase in size, and like the 

 protoplasm contained in the spores is always coloured yellow by iodine in this species. 

 The protoplasm of the ascus before the spores are formed, and that within the spores 

 at all times, shows the same reaction with iodine in Peziza confluens. But after the 

 orientation of the spores the protoplasm of the ascus shows the characters of a 

 substance, for which I formerly proposed the name of epiplasm, and which is dis- 

 tinguished from ordinary protoplasm by being more highly refringent, by its peculiar 



Fig. 39. Peziza [Pyronema) cojiftnens, P. a a small portion of the hymenium ; p a paraphysis, which is only attached 

 to the hyphal branches from which the three asci spring without originating- in them, r — 10 full-grown asci, the successive 

 stages of the development in the order of the letters ; in ;- — it the nuclei are multiplying, in v the spores are being formed, 

 in 7v they are mature, m young asci. Magn. 390 times. 



homogeneous and glistening appearance, and especially by the reddish brown or violet 

 brown colour which it assumes when treated with very dilute solution of iodine. 

 Errera 1 has recently shown that this reaction with iodine is due to the circumstance 

 that the epiplasm contains a relatively large quantity of glycogen permeating a 

 protoplasmic or albuminoid vehicle ; the term glycogen-mass, or shortly glycogen, 

 may therefore be substituted for that of epiplasm. 



In some other species with large asci (Peziza convexula, P. Acetabulum 2 , and 

 P. melaena, Helvella esculenta, H. elastica, and M orchella esculenta) the contents of the 

 ascus which are at first uniform are differentiated before the spores are formed into 

 protoplasm and glycogen-mass. The former aggregates in Peziza convexula into a 



1 See above on page 6. 



2 The species named Peziza sulcata ? in my work on the Asycomycetes belongs to P. Acetabulum. 



