188 



MEDICAL MYCOLOGY 



This family is characterized by the rim around tlie spore, producing a 

 cucullate spore if the rim is on one side, or a saturnine spore if the ring is 

 equatorial. Within the family there is a large isogamous series and a small 

 heterogamous one. 



In the heterogamous series, which seems to be the more primitive, we 

 have Endoniyces Magnusii {Magnusiomyces) from the slime flux of trees (Fig. 

 18). The hyphae are generally multinucleate (2-8). In growing hyplial tips 

 this number may mount to 50 (Pig. 18, 1), in weak hyphae it may be as low 

 as one. The hyphae divide easily into oidia ; Avliich are generally multinucleate, 

 rarely uninucleate. In successive divisions the tendency is toward the uninu- 

 cleate condition. Often their wall thickens and the oidia become hypnospores 



Fig. 18. — Endomyces Magnusii. 1, young- multinucleate hypha ; 2, older hypha ; 3-9, 

 II, development of asci ; 10, hvpnospores. {1, 2, 10 xl.500; S-9, 11 X500.) (After Guillier- 

 mond 1909.) 



(Fig. 18, 10) ; with the consequence that, under certain environmental con- 

 ditions, a culture may disintegrate into hypnospores after a couple of weeks. 



With favorable conditions, oidia may develop to sprout mycelia, not by 

 independent development of small outgrowths of the mother cell to sprout 

 cells but by fission of the mother cell. Both daughter cells round oft' and 

 develop to the size of the mother cell (ordinary cell division in contrast to 

 sprouting). 



When the mycelium is ready to form asci, it divides into numerous short, 

 slender branches with short cells containing few nuclei, often not more than 

 one (Fig. 18, 3, and 4). A branch ends either in a very large cell full of 

 reserves, the ascogouium, or in a narrow hyaline cell, often much twisted, the 

 antheridium. The upper third of the ascogonium swells considerably and 



