174 THE GASTEROMYCETES OF THE UNITED STATES AND CANADA 



p. 194) expresses the surprising opinion that these plants are related to Tylostoma 

 and represent a compound group of Tylostoma fruit bodies enclosed in a common sheath. 



Literature 



Andrews. Notes on a Species of Cyalhus common in Lawns at Middleburg, Vermont. Rhodora 2: 



99, pi. 17. 1900. 

 Brefeld. Botanische Untersuchungen iiber Schimmelpilze 3: 176. 1877. 

 Cunningham. A Revision of the New Zealand Nidulariales, or "Birds-nest Fungi." Trans. New 



Zealand Institute 55: 59, pis. 3 and 4. 1924. 

 Eidam. Die Keimung der Sporen und die Eutstehung der Fruchtkorper bei den Nidularieen. Cohn's 



Beitrage der Pflanzen 2: 221. 1877. 

 Fischer. 1. c, in Pflanzenfamilien, p. 324, which see for other literature. 

 Fries, R. E. Om utvecklingen af fruktkroppen och peridiolerna hos Nidularia. Svensk bot. Tidskr. 



4: 126, one plate. 1910. 

 Fries, R. E. Ueber die cytologischen Verhaltnisse bei der sporenbildung von Nidularia. Zeitschr. 



Bot. 3: 145, pis. 1 and 2. 1911. 

 Hesse. Keimung der Sporen von Cyathus strialus Willd., einer Gastromycetenspecies. Jahrb. Wiss. 



Bot. 10: 199. 1876. 

 Lloyd. The Nidulariaceae, figs. 1-20 and pis. 102-111. Cincinnati, 1906 

 Maire. Recherches cytologiques et taxonomiques sur les basidiomycetes. Bull. Soc. Myc. France 18: 



178 (of supplement), pi. 6. 1902. 

 Martin. Basidia and Spores of the Nidulariaceae. Mycologia 19: 239, pis. 22, 23. 1927. 

 Mollaird. Le cycle de deveioppement du Crucibuhim mdgare Tul. et de quelques Champignons supen- 



eurs obtenu en cultures pures. Bull. Soc. Bot. France 56: 91. 1909. 

 Sachs. Morphologie des Crucibuhim vulgare Tulasne. Bot. Zeit. 13: 833, pis. 13, 14. 1855. 

 Tulasne, L. R. and Ch. Recherches sur l'organisation et le mode de fructification des Champignons 



de la tribu des Nidulariees. Arm. Sci. Nat., 3rd ser., 1: 41. 1844. 

 Walker. Development of Cyathus fascicularis, C. striatus, and Crucibuhim vulgare. Bot. Gaz. 70: 



1, pis. 1-6 and 3 figs. 1920. 

 White. The Nidulariaceae of North America. Bull. Torr. Bot. Club 29: 251, pis. 14-18. 1902. 



Key to the Genera 



Peridioles (or most of them) attached by cords to the cups 



Peridium cup-shaped with a thick wall composed of a single layer; peridioles whitish from the thick 



white tunica Crucibuhim (p. 181) 



Peridium bell-shaped or goblet-shaped, with walls of three obvious layers; peridioles gray or nearly 



black; tunica thin or wanting Cyathus (p. 174) 



Peridioles not attached by cords, but embedded when fresh in a mucus 



Peridium thin, spherical, falling into fragments Nidularia (p. 183) 



Peridium thick, cup-shaped, opening at the top Nidula 



CYATHUS Haller 



Plants distinctly bell-shaped or goblet-shaped; the tough peridium composed of 

 three distinct layers, in expanding towards maturity exposing a thin, pale, usually 

 almost smooth epiphram which is stretched across the top and which disappears with 

 age. Peridioles attached by a cord, black or dark brown, in some cases covered with a 

 very thin tunica, which, however, does not completely hide their dark color. Basidia 

 not forming a distinct or homogeneous hymenium, but scattered at irregular heights 

 throughout a large central area and intermingled with numerous delicate threads which 

 at maturity have their cell walls greatly thickened and gelatinized to form a solid horny 

 matrix, throughout which the spores are unevenly scattered. At the time the spores 

 are growing, this matrix is not horny but gelatinous, becoming horny at maturity. 



