150 MYCOLOGY 



scribed later. It attacks the roots of a large series of plants including 

 the tobacco, at least 105 species of plants being attacked according to 

 the latest account.^ The parasitic mycelium is intercellular, abun- 

 dantly septate and hyaline. It produces conidiospores, which are 

 abjointed acrogenously from the conidiophore, and are not as was 

 supposed formerly endospores formed by free cell division within an 

 endoconidial cell. The first conidiospore is liberated by the differentia- 

 tion of its walls into an inner wall and a sheath and by the rupture of 

 the latter at its apex. The later conidiospores grow out through the 

 sheath of the first and are freed by a spHtting of their basal walls.- This 

 same process is probably that of all " endoconidia " in fungi. 



Family 3. Elaphomycetace^. — The fruit bodies of the fungi of 

 this family are subterranean with a distinct, mostly thick peridium 

 whose surface is marked by a more or less strongly developed rind. The 

 asci borne within the closed fruit body are irregularly arranged and 

 united into large groups, which are separated by radially arranged vein- 

 like masses of sterile hyphae. The asci are spheric, or pyriform, and 

 mostly eight-spored. The whole spore-bearing interior of the fruit 

 body, when ripe, is transformed into a powdery mass with the sterile 

 hyphae remaining as a number of capillitia-Hke threads. There is no 

 spontaneous opening of the fruit body at maturity. The family in- 

 cludes a single genus, Elaphomyces, which comprises about twenty-two 

 species, found mostly in northern Italy, in Germany and France, a few 

 in England, northern Europe and North America. Such species, as 

 Elaphomyces papillalus, E. atropurpureus from the oak and chestnut 

 woods of northern Italy, E. mutabilis with a silvery-white mycelium 

 growing in the oak, beech and birch woods of northern Italy, France 

 and Germany, E. citrinus with an orange-yellow mycelium, also from 

 northern Italy, all have delicate thin rinds which become wrinkled 

 when dry, and belong to the section Malacodermei. The section Sclero- 

 dermei includes those species with compact brittle rind, which is not 

 wrinkled when dry. Here belong E. maculatus with strongly de- 

 veloped, green myceUum, surface of fruit body blackish brown with 

 greenish markings, found in the oak forests of northern Italy, French 



1 Johnson, James: Host Plants of Thielavia basicola. Journ. Agric. Res., 

 vii: 289-300, Nov. 6, 19 16. 



^ Brierley, William B.: The Endoconidia of Thielavia basicola; Zopf, W., 

 Vnnals of Botany, xxix: 483-491, with i plate, October, 1915. 



