[Vol. 9 



148 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



460 u, rarely larger, in diameter, sharply angular in outline, with 

 faces smooth or marked with large low tubercles; microspores 

 fawn-colored, chiefly 27-39 p long, mostly spinulose. 



Distribution: Chihuahua, Hidalgo, Mexico, Morelos. 



Specimens examined : 



Mexico: wet places, pine plains, base of Sierra Madre, State of 



Chihuahua, 6 October, 1887, Pringle 1447 (U. S. Nat. Herb, 

 and Gray Herb.), type; wet places, base of Sierra Madre, 

 10 October, 1888, Pringle 1713 (Mo. Bot. Gard. Herb.); 

 Canales Station, State of Hidalgo, 29 September, 1904, Prin- 

 gle 8796 (Mo. Bot. Gard. Herb., Gray Herb., and U. S. Nat. 

 Herb.); wet soil, borders of shallow ponds, plains near Flor 

 de Maria, State of Mexico, 28 August, 1890, Pringle 8459 

 (Mo. Bot. Gard. Herb, and U. S. Nat. Herb.) ; shallow pools, 

 Sierra de las Cruces, alt. 9500 ft., State of Mexico, 24 August, 

 1904, Pringle 13261 (U. S. Nat. Herb, and Gray Herb.); 

 shallow water near Cuernavaca, State of Morelos, 22 August, 



1897, 



Gard. Herb., Gray Herb., and 



U. S. Nat. Herb.) ; "torrent qui descende de Monte San Mi- 

 guel, vers Lama de la Huerta," alt. 2200 m., vicinity of 

 Morelia, State Michoacan, 10 November, 1910, Bro. G. 

 Arsene 3653 (U. S. Nat. Herb.). 



The species is variable in habit, ranging to almost terrestrial, 

 from the appearance of herbarium material. The species /. 

 Montezumae was based on material collected by Pringle in 

 the states of Mexico and Morelos. The distinctive difference 

 in the herbarium specimens lies in the presence of tiny basal 

 scales in some of this material. Since there is variability in this 

 feature in other forms, as I. Nuttallii A. Br., probably in accord- 

 ance with the amount of moisture present, and since the 

 plants growing in shallow water fail to show such persistent 

 leaf-bases, the character is considered ecological. The species 

 is accordingly reduced. 



ngle's No. 18261 is unusual in showing 

 3 p in diameter, but otherwise agrees wi 

 collected from the soil, but snores from 



These 



520 [i, outside the range shown by any other mater 



available 



