A. W. Evmis — North American Species of Fndlania. 19 



with acute lobes and sinus, entire or irregularly dentate on the sides ; 

 perianth obovate or obcuneate, more or less compressed, abruptly 

 narrowed into a short, broad beak, with a distinct, sometimes two- 

 angled postical keel but withoyit distinct supplementary ridges, 

 smooth or slightly roughened on lateral keels, never tuberculate : 

 5 spike oblong, occupying a short lateral branch, bracts in many 

 pairs. 



Stem O'lO™"" in diameter, lobes of leaves 0'45™"^ long and wide, 

 lobules 0-21'"'" long and wide ; underleaves 0-20""'° long, 0-15"^" wide; 

 leaf-cells from edge of lobe 0-014™'", from middle 0-OlV""" in diame- 

 ter, and from base O-OSO""" long, O-Ol?""™ wide; bract I, lobe 0-80°"" 

 long, 0-45°"" wide, lobule O-GO"""^ long, 0-30™'" wide ; bracteole I, 

 O-SS'"™ long, 0-23"'» wide ; bract II, lobe 0-60'"'^^ long, O-SS'""" wide, 

 lobule 0-45"^'" long, 0-18"'" wide; bracteole II, 0-45"^'" long, 0-15"°^ 

 Avide ; perianth I-IO""-" long, 0-75"^°^ wide. 



On trees and rocks ; from Canada to Florida and westward to 

 Minnesota : very common in the mountains and in northern regions. 

 Distributed in Hep. Bor.-Amer. n. 105, in Hep. Amer. n. 27, and in 

 Can. Hep. n. 1. 



Frxdlania Ehoracensis is characteristically a northern species and 

 reaches the south only as a rarity, whereas the reverse is true for F. 

 Virginica. In a sterile condition the two species sometimes resemble 

 each other so closely that it is difBcult if not impossible to tell them 

 apart and we must depend upon periajiths for differential chai-acters 

 which are constant. The perianth of F. Ehoracensis is very variable 

 both in shape and in the character of the postical keel, but it has the 

 unusual feature among Trachycolem of being smooth and without 

 supplementary ridges. In some cases, however, there is a slight 

 trace of an antical ridge, although this seems to be an exceptional 

 condition, F. Virginica is of course distinguished by its tuberculate 

 perianth with distinct supplementary ridges. 



Subgenus III.— HOMOTROPANTHA Spruce. 



Represented by the single species: — 

 11. FruUania plana SuUiv., Mem. Amer. Acad., new series, iv: 175. 1849. 

 Plate IX. figs. 12-21. 



Autoicous : plants growing in wide depressed tufts, green, some- 

 times tinged with brown : stems irregularly pinnate or bipinnate : 

 leaves imbricated, the lobe orbicular, arching over the stem and 

 strongly cordate or auriculate at the base, decurved at the rounded 

 apex, entire ; lobule galeate, close to the stem, truncate at base , 

 inflated particularly in upper and outer parts, stylus minute : under- 



