168 



COMPARATIVE MORPHOLOGY OF FUNGI 



maceae, they are divided into sterile stipes and fertile heads. In the 

 Trichocomaceae, the sterile veins have intertwined to faveolate structures 

 open at the top. In the Terfeziaceae and Elaphomycetaceae, they have 

 developed to truffle-like, hypogaeous structures which in the former are 

 soft and degenerate as a whole, in the latter surrounded by hard, resistent 

 peridium, the gleba breaking down into a dusty spore mass with 

 capillitium. 



The diagrammatic representation of the morphological relationships 

 between these families is given in the summary at the close of the order. 



Gymnoascaceae. — The simplest member of this group to be studied 

 cytologically, Amauroascus verrucosus (Dangeard, 1907), is generally 

 closely connected to Eremascus. On its substrate, garbage and dung, it 

 forms a white arachnoid covering which thickens in places to small white 

 knobs, 'the fundaments of fructifications. From any two hyphae multi- 

 nucleate copulation branches are formed and basally abjointed (Fig. 103, 



Fig. 104. — Gymnoascus Rcessii. 1. Small fructification; a, vegetative hyphae. b, loose 

 peridium which surrounds the ascigerous tissue. 2. Group of asci. 3. Mature ascus. 

 After Brefeld, 1891 and Baranetzky, 1872.) 



1 and 2). One branch, the antheridium, is vertical and somewhat the 

 stronger; the other, the ascogonium, is somewhat slenderer and is coiled 

 around the antheridium in a helix. A solution of the separating wall 

 at the tip of both organs and nuclear migration has not yet been observed. 

 The ascogonium continues its growth and branches often (Fig. 103, 3 and 

 4). The branches coil spirally (Fig. 103, 5) and after a certain time 

 divide into binucleate cells which swell to eight-spored asci (Fig. 103, 

 6 and 7). 



Meanwhile this knob of ascogenous nyphae is surrounded by a 

 compact, sterile, hyphal tissue, so that the asci are imbedded in a loose 

 brownish hyphal cushion, which is the simplest form of a fructification 

 (perithecium). 



In Gymnoascus the hyphal sheath possesses a more marked peridial 

 character. Gymnoascus is saprophytic on earth, on offal, dung, cadavers, 

 etc., and forms a fluffy, occasionally brightly colored, covering on the 



