THE PLANT WOKLD 125 



hollow, equal, ocliraceous, even, glabrous, 6cm. long, 4mm. thick; capil- 

 litium threads hyaline, thick- walled, branched, 5mm. in diameter; spores 

 globose, pale yellow-brown, minutely warted, 5-6/z. in diameter. 

 " On the ground, Eio Grande, north Mexico." Said to be distinguished 

 from T. Meyenianm by its entire mouth and hollow even stem. 



Tylostoma campestre Morgan. Inner peridium depressed-globose, 

 somewhat squamulose, submembranaceous, becoming smooth and white, 

 12-18mm, in diameter; mouth plane, irregular, lacerate but not fimbri- 

 ate; stipe 2-3cm. long, about 6mm. thick, subequal, brownish, squam- 

 ose; capillitum threads long, slender, hyaline, branched; spores irreg- 

 ularly globose, pale brown, minutely warted, 4.4-5.5/". Sandy soil, Ne- 

 braska and California. 



Tylostoma punctatum Peck. Peridium about 1.3cm. in diameter, 

 subglobose, flattened and umbilicate at the base, papery but firm and 

 tough, minutely and irregularly punctate-pitted, whitish, remains of 

 the outer peridium persistent about the base; mouth slightly promi- 

 nent, small, lacerate; stem about 3mm. thick and 3cm. long, cylindrical, 

 obscurely scaly or rimose-scaly, sulcate-striate above, hollow, subferru- 

 ginous, white wdthin; capillitium threads hyaline, sparsely branched, 

 broader than the spore, ends obtuse, subtruncate or sometimes thick- 

 ened; spores globose, 4-5/^, pale ferruginous, minutely warted or rough- 

 ened. Sandy ground, Kansas. 



Tylostoma semisulcatum Peck. Peridium subglobose, longer than 

 broad, 1.3-1.5cm. broad, 1.7cm. long, glabrous above, ferruginous tomen- 

 tose on the lower half; mouth entire; stem about 5cm. long, even and 

 glabrous or slightly furfuraceous near the top, the lower part longitu- 

 dinally sulcate, whitish; spores globose, ferruginous, 4-5/*; capillitium 

 threads non-septate, colorless. Sandy soil, Nevada. 



GEASTEE Mich. 



Outer peridium rather thick, sometimes composed of two layers, 

 dividing in a stellate manner into several segments which break away 

 from the inner peridium and become spread out or reflexed; inner per- 

 idium thinner, dehiscing by a regular mouth at the apex. 



Synopsis of the Species. 



I. Inner peridium with a short pedicel. 



A. Mouth sulcate-plicate. 



a. Surface of the inner peridium minutely warted G. campestHs. 



b. Surface of the inner peridium smooth. 



a. Outer peridium of two layers. 



X. The two layers separating nearly to the tips 



of the segments. G. fornicatus. 



XX. The two layers separating only near the 



center. G. tm-binatus. 



b. Outer peridium of one layer. G. bryantii. 



B. Mouth ciliate-fimbriate. 



a. Inner peridium subglobose, brownish. G. limbatus. 



b. Inner peridium ovoid, white. G. niijiiiims. 



