ASCOBOLUS. 329 



in the preparation young asci which, besides the spores, show 

 also a protoplasmic residue the epi plasm. During the ripening 

 of the spores this dwindles to a thin lining layer. The tip of the 

 ripe ascus projects above the surface of the hymenium. On its 

 flattened apex a small circular cover is clearly recognisable. 

 This is opened for the discharge of the spores, the expulsion of 

 which is brought about by a strong tension upon the walls of 

 the ascus, due to a strongly swelling substance surrounding the 

 spores. It is this substance, also, which so greatly stretches the 

 ascus that its apex protrudes from the hymenium ; the empty 

 collapsed asci are withdrawn into the hymenium. 



The paraph yses are long, much septate threads. Their 

 terminal segments are swollen club- wise ; their contents are 

 sparse and colourless. Asci and paraphyses are in their upper 

 part embedded in a gelatinous substance of a sulphur yellow 

 colour, and it is this which gives to the entire fructification its 

 yellow hue. This likewise proceeds from the swollen membranes. 



On the addition of normal iodine solution the hymenium, in its 

 lower parts, takes on a blue colour, a phenomenon which rarely 

 comes with the Fungi, but is widely spread amongst Lichens. 

 These latter, in point of fact, are also, like Ascobolus, almost 

 always Ascomycetes, but living symbiotically with Algae. The 

 red-brown staining of the epiplasm x in the asci appears here less 

 beautifully than in Morchella. According to the colour of their 

 walls the spores take, at the same time, a light brown to a dark 

 brown colour. By the aid of their gelatinous appendage the 

 spores remain clinging to the substratum against which they 

 happen to have been propelled. The spores do not, however, 

 germinate, but, as researches have shown, must pass into the 

 intestines of an animal in order to become capable of germination. 



The formation of the fructification of the Ascomycetes results 

 from a sexual act, 1 As a first rudiment, an oogonium and an 

 antheridium are present. After the union of the oouucleus w r ith 

 the male spermonucleus, the oogonium grows to a thick multi- 

 cellular thread, a cell of which swells, and, in Sphcerotheca, 

 develops direct into the ascus, of which but one is present in a 

 fructification ; in Ascobolus, on the contrary, a branched thread 

 arises from it, which finally develops the asci. The young asci 

 are mostly multinuclear ; in Splicerotheca two, in Ascobolus four 

 nuclei. These original nuclei, however, combine with one another 

 1 This has been proved in a few Genera only. [Ed.] 



