150 THE GASTEROMYCETES OF THE UNITED STATES AND CANADA 



Basidia short-clavate, usually 4-spored, peculiar in having the spores scattered over the 

 surface. There is no trace of a hymenium or of tramal plates, the basidia being dis- 

 tributed equally on the interwoven threads of the homogeneous gleba. Spores spherical 

 or subspherical, rust colored to cinnamon, warted or smooth. 



The genus is distinguished from others of the family by the smaller size and (except 

 in Chlamydopus) by the definite, circular, smooth or fimbriated apical mouth (or 

 mouths) by which the inner peridium opens to liberate the spores. Miss White reports 

 seventeen species from North America, eight of which are described as new. Tulostoma 

 is the spelling used by some authors, and Tulasnodea Fr. is a synonym. 



In the unexpanded button the stem is a short plug enclosed in the outer peridium. 

 When the expanded plant dries the stem shrinks considerably in thickness and draws 

 away from the outer peridium which surrounds it above. This leaves a space between 

 the two, and the descending margin of the outer peridium which is often acute is the 

 so-called collar around the stem apex. If moistened after drying the stem swells back 

 to its original size and fills the collar again. The spores are often somewhat collapsed 

 when dry so that even those that were smooth when fresh may appear angular or 

 nodulated. In such cases they should be plumped out by an application of KOH or 

 lactic acid. 



Literature 



Bessey. Growth of Tulostoma mammosum. Amer. Nat. 21: 665. 1887. 



Lloyd. Myc. Notes, p. 133, pis. 10 and 11 and text figs. 66,67. 1903. 



Lloyd. The Tylostomeae, figs. 1-6 and pis. 20 and 74-85. 1906. 



Morgan. Journ. Cin. Soc. Nat. Hist. 12: 163, pi. 16, figs. 1-5. 1890. 



Petri. Sul valore diagnostico del capillizio nel genere "Tylostoma" Pers. Ann. Myc. 2: 412, pi. 6. 



1904. 

 Petri. Flora Italica Cryptogama (Gasteralesl, Fasc. 5: 115. 1909. 

 Schroeter. Ueber die Entwickelung und die systematische Stellung von Tulostoma Pers. Cohn's 



Beitrage sur Biologie der Pfianzen 2: 65, 1 text fig. 1877. 

 White. The Tylostomaceae of North America. Bull. Torr. Bot. Club 28: 421, pis. 31-40. 1901. 



For other literature see p. 194. 



Key to the Species 



Mouth projecting as a circular glabrous tube with a sharp edge 



Spores nearly smooth T. mammosum (p. 151) 



Spores distinctly warted 



\T. simulans (p. 151) 

 '\T.floi 



Spore sac not warted \j. fioridonwn (p. 153) 



Spore sac warted T. verrucosum (p. 153) 



Mouth less projecting, sometimes not at all so, edge not composed of a fibrous roll; often elliptical or 



linear; more than one mouth often present 



Spores smooth, minute, 2-3/i T. Finkii (p. 154) 



Spores smooth, larger, 4.2-5.5 x 5-7.4/1 T. vohulatum (p. 155) 



Mouth appearing in the center of a slightly elevated fibrous mat, its edge eroded and fibrous unless 



much worn 

 Spores smooth 



Spore sac pale T. poculalum (p. 155) 



Spore sac reddish brown, stem very long T. Lloydii (p. 156) 



Spores minutely warted T. campestre (p. 156) 



Spores distinctly warted T. Berkeleyii (p. 157) 



