- 69 - 



much wider, thick-walled and near costa, mostly pitted. Capsule oblong- 

 cylindrical, not quite symmetrical, with conical lid I its length and broad 

 annulus of 3 rows of cells. Three or 4 rows of elongated cells about mouth 

 of capsule, below the cells becoming irregularly oblong to rectangular, 

 mostly 2-4 times longer than wide. Teeth pale, very papillose, rather broad 

 and irregular, without distinct articulations. (Plate 15). 



This plant is closely related to flexicaule with which it has been associ- 

 ated both in this country and Europe, and some of the larger forms of flexi. 

 caule approach it very closely but I have not yet seen any wnth such long, 

 slender, serrulate leaves with inner perichsetial leaf truncately narrowed to 

 so dentate a subula. The color and size alone are usually sufficient to sepa- 

 rate the plant. Macoun's no. 66 is this species, also Leiberg's 232. In Eu- 

 ropean collections, "485 Jack, Leiner and Sitzenberger Kryp. Badens," "a" 

 is this and "c" is fiexicattle. 1307 Rabenhorst, Bry. Eur. looks much like 

 this but is Dicranodo7iiium. "iii Bryotheca Silesiaca" and " 11 1 Wilson, 

 Musci Brit." are this species. 



Sterile specimens only were collected at Dawson. The description is 

 drawn up from specimens collected at Columbia Falls, Mont., July, 1892. In 

 the plate the teeth are probably figured too short, the only available speci- 

 men being in poor condition. The plant grows on both earth and rock and 

 rarely fruits (568). 



Bryobrittonia R. S. Williams, gen. nov. 



Closely related to Tortula and Des7natodon from which it is distin- 

 guished by the mamillose leaves, the exposed surfaces of the distinct cells 

 being highly convex. From Trichostoiiium and Timmiella it is distin- 

 guished by the costa with only one stereid band; the first of these also has 

 the leaves smooth or papillose and the second has a leaf lamina of 2 layers 

 of cells, mamillose on the upper surface only. 



This genus is dedicated to Mrs. Elizabeth G. Britton, by whose aid so 

 many American students of our mosses have been encouraged. 

 Bryobrittonia pellucida S. R. Williams, sp. nov. 



With much the habit of Tortula latifolia but leaves much longer and 

 narrower above. Stems mostly simple, radiculose below, in loose, rather 

 dark green tufts up to 2 cm. high, in cross-section irregularly oval (about .320 

 mm. long) with walls of 2 or 3 rows of slightly thickened irregular cells, 

 ground tissue of large thin-walled cells, surrounding a distinct central 

 strand of numerous small thin-walled cells. Terminal leaves (often enclos- 

 ing numerous long paraphyses-like hairs) oblong lanceolate, up to 7.5 mm. 

 long and 1.5 mm. broad, plicate and somewhat crispate when dry or rarely 

 nearly straight, mamillose on both faces except dorsal ^ide of costa, crenu- 

 late-serrate on fiat borders in upper half, obtusely or somewhat acutely 

 pointed, with stout costa (.140 mm. wide near base) long-decurrent on stems 

 and vanishing several cells below apex. Lower leaves ovate-oblong (about 

 3 mm. long). Leaf-cells above rhomboidal to hexagonal, about .016 mm. in 

 diameter, becoming gradually elongated below and hyaline, the cells near 

 margin a little above base .004-. 006 mm. wide and up to .160 long, toward 



