2 54 Alexander W. Evans, 



the margin ; appendages of median scales oblong, ovate, or ovate- 

 orbicular, mostly 0.6-0.75 mm. long and 0.45-0.6 mm. wide, 

 usually narrowed toward the rounded, obtuse or acute apex, 

 margin entire or vaguely and irregularly denticulate or dentate, 

 rarely with a basal lobe, cells showing a slight and gradual 

 decrease in size toward the margin, median cells isodiametric to 

 distinctly longer than broad, mostly 25-60/i, long and 20-30/x wide, 

 marginal cells mostly 30-40/x long and 12-20/A wide, very irregular, 

 the long axis sometimes parallel with the margin and sometimes 

 at an angle with it, cells containing oil-bodies sometimes absent 

 altogether, when present about 20/i, in diameter, one to three or 

 more in number and indefinite in position : male receptacle borne 

 on a stalk 5-7 mm. high, with two rhizoid-furrows, destitute of 

 dorsal air-chambers, the disc 5-6 mm. broad, very shortly or 

 sometimes (according to Schiffner) more deeply eight- (to 

 twelve-) lobed, the lobes or rays rounded and with a thin wavy 

 margin, ventral scales restricted to middle portion of disc : female 

 receptacle borne on a stalk 2-4 cm. high, with two rhizoid-furrows 

 and a single broad dorsal band of air-chambers, the disc about 

 0.5. cm. broad, usually nine-lobed, the lobes or rays spreading at 

 maturity, 0.8-1.2 mm. long, separated by subequal sinuses or with- 

 the deep sinus between the basal ray broader than the others, 

 flat, dilated at the truncate or emarginate apex, disc with a median 

 hemispherical or papilliform protuberance about 0.5 mm. in 

 diameter and nine distinct ridges corresponding with the rays ; 

 involucre much as in M. polymorpha: spores brownish yellow, 

 about 34ju, in diameter, with a narrow hyaline margin about 2fx 

 wide, outer face bearing a series of low lamellae sometimes form- 

 ing an indistinct reticulum ; elaters mostly 6-8ju, wide, bispiral ; 

 cupules with toothed lobes much as in M. polymorpha, but lacking 

 epidermal papillae. (Figs. 6-8.) 



A widely distributed species in tropical and subtropical regions. 

 The following North American specimens have been examined : 



Arizona: Huachuca Mountains, 1910, L. N. Gooding 824 

 (N. Y.). 



Puebla: Puebla, 1906, Frere Arsene (N. Y.) ; Honey Station, 

 October, 1908, Barnes & Land ^oj (Y.) ; banks along Avenida 

 Hidalgo and path to barranca, Tezuitlan, Barnes & Land 544 

 (Y.) ; Santa Barbara, near Puebla, November, 1909, Frcre 

 Nicolas 2 (Y.). 



Vera Cruz: Orizaba, 1855, F. Midler 2245 in part (N. Y.) ; 

 walls of Lost River sink, Orizaba, November, 1908, Barnes & 

 Land 668 (Y.). 



Guatemala: Coban, Alta Verapaz, 1310 m. alt., 1892, H. von 

 Tuerckheim 4p6o (N. Y.). 



