170 COMPARATIVE MORPHOLOGY OF FUNGI 



As in Amauroascus, the ascogonium winds helically around the anther- 

 idium; in contrast to Amauroascus, the separating wall at the tip is dis- 

 solved and the male nucleus migrates into the ascogonium. This is 

 divided by septa into binucleate (?) cells which develop to ascogenous 

 hyphae on which arise, terminally or laterally, the eight-spored asci. 

 Meanwhile the sexual organs have become surrounded by a loose hyphal 

 tissue (Fig. 104, 1) whose peripheral hyphae form peculiar lateral 

 spines and whose membranes thicken and turn brown at maturity (Eidam, 

 1883; Dale, 1903). 



The most compactly built rind is found in Ctenomyces. Its only well- 

 known species, C. serratus, found on decaying feathers in henyards, forms 

 hyphal tissue, hyaline when young, whose hyphae abjoint laterally numer- 

 ous oval hyaline conidia. The cells of the hyphae are 1 to 4 nucleate, the 

 conidia (Fig. 105, C) are generally uninucleate. The conidiophore hyphae 

 may branch in fascicles and may finally come together to pycnidia-like 

 masses in which the conidiophore hyphae later swell, filling the cavity 

 with a slimy conidial mass. 



The young copulation branches are 1 to 3 nucleate, the male branch 

 develops to a vertical clavate structure which finally contains 10 to 12 

 nuclei (Fig. 105, D) . The ascogonium winds 6 to 7 times about the anther- 

 idium and finally contains about 20 nuclei. A solution of the separating 

 wall and nuclear migration has not been observed. Without further proc- 

 esses the ascogonium divides into binucleate almost isodiametric cells; 

 these develop to ascogenous hyphae which again coil helically and sur- 

 round the original helix. From this confusion, the eight-spored asci 

 arise in an unknown manner. Meanwhile the whole knob is closely sur- 

 rounded by sterile hyphae which, with considerable thickening of their 

 walls, become moniliform and partly develop on one side to peculiar short 



processes. 



Besides these perithecia, light brown sclerotia are also formed on the 

 feathers. The cells in the vicinity of the septa are nodose (Fig. 105, B). 

 From these there arise unusual pectinate, falcate or setiform hyphae, 

 whose unguiform processes are turned in the same direction. Possibly 

 they serve to disseminate the sclerotia by clinging to foreign bodies 

 (Eidam, 1883; Matruchot and Dassonville, 1899; Dangeard, 1907). 

 These falcate and other structures of Ctenomyces are strikingly reminis- 

 cent of certain imperfect genera, as Trichophyton, Microsporum and 

 Achorion, which cause ringworm, favus and other skin and hair diseases 

 in men and animals. It has become probable through the investigations 

 of Matruchot and Dassonville (1899a, 1901 ; Grigoraki, 1925) and others 

 that these imperfect genera belong to the Gymnoascaceae, i.e., to 

 Ctenomyces and the closely related Eidamella. 



Aspergillaceae — The simplest member of the Aspergillaceae, Aphan- 

 oascus cinnabarinus, is directly connected to the Gymnoascaceae. Like 



