American Species of MarcJiantia. 271 



surface of disc and rays usually plane but sometimes more or less 

 convex, basal sinus broader than the others and sometimes form- 

 ing a very obtuse angle ; involucre very delicate, the margin 

 minutely and often irregularly crenulate to short-ciliate, the teeth 

 usually varying from one to three cells in length ; spores brown- 

 ish yellow, about 28yu in diameter, the outer face bearing a series 

 of low irregular ridges not forming a network ; elaters about 6/x 

 wide, bispiral : cupules closely short-ciliate, the cilia mostly one 

 to four cells long, outer surface without papillae. (Figs. 10-12.) 



A widely distributed species in the southern United States, the 

 West Indies, Mexico, Central America, and Venezuela. The fol- 

 lowing specimens have been examined : 



Tennessee: Etowah, June, 1909, F. McCormick (C. C. H., 

 Y., listed as M. disjuncta by tlie writer in Bryologist 13 : 33. 

 1910). 



Georgia: west bank of Ocmulgee River, Hawkinsville, June, 

 1902, R. M. Harper 1^8 2a (N. Y., U. S.) ; Samochechobee Creek, 

 near Killen, Clay County, October, 1902, R. M. Harper lygih 

 (N. Y., U. S.) ; Flint River swamp, below Albany, Dougherty 

 County, August, 1903, R. M. Harper ipjie (N. Y., U. S.). 



Florida : Devil's Millhopper, Alachua County, February, 1909, 

 R. M. Harper 14 (N. Y.) ; April, 1915, N. L. T. Nelson 45, 46, 

 47,51 (Y.). 



Alabama: banks of the Alabama River near Claiborne, 

 JV. S. Sullivant (H., type locality of M. disjuncta, specimens 

 distributed in Muse. Alleg. 286 and Hep. Bor.-Amer. 128) ; 

 Auburn, May, 1896, L. M. Underwood (N. Y., Y., distributed, as 

 M. disjuncta, in Hep. Amer. 182) ; June, 1897, Earle & Baker 

 52 (N. Y.). 



Texas: Fort Worth, 1887, G. S. Thompson 10 (N. Y., U. S., 

 listed as M. disjuncta by Underwood in Bot. Gaz. 20: 69. 1895) ; 

 Hallettsville, May, 1892, G. C. Nealley 59 (C. C. H., U. S.) ; 

 Austin, March, 1909, F. D. Heald (Y.). * 



Arkansas: Fort Harvey, no date, F. L. Harvey 2 (N. Y., 

 listed as M. disjuncta by Underwood, I. c). 



Mexico : without definite locality or date, C. H. Schidtz 1229 

 (B., listed as M. papillata, by Stephani in Bull. Herb. Boissier 

 7:397. 1899). 



Hidalgo: Tula, C. G. Pringle io6/j (Y., distributed in PI. 

 Mex. under a manuscript name of Stephani). 



