81 
EUTHUIDIUM: Stem-leaves and branch-leaves heteromor- 
phous, papillate on both surfaces; leaf-cells quadrate-hexagonal 
to oblong-rhomboidal; paraphyllia simple or multiform. 
1. THuiprum pyGMAEuM Br. & Sch. 
Thuidium pygmacum Br. and Sch. Bryol. Eu. fasc. 49-51: ©. 
1852. 
Flypnum pygmaeum Sull. Mosses U.S. 67. 1856. 
‘Plants very smail, dirty green in felt-like mats; stem I to 2 
cm. long, creeping, pinnately branched; branches pinnate, capil- 
lary, subcompressed, papillate; paraphyllia sémple, short, 2 to 5 
cells long; stem-leaves triangular-ovate, narrowly acuminate, dis- 
tant; leaf-cells quadrate-hexagonal (.006 mm.) pluripapillate; 
branch leaves (.15 mm) ovate, obtuse, appressed-incurved when 
dry. Monoicous; perichetial bracts erect, lanceolate or oblong- 
lanceolate, entire or serrulate above; pedicel long, flexuous; cap- 
sule oblong, zzeguilatcral, inclined or horizontal, wide-mouthed; 
annulus broad, compound; cilia 2 to 3; operculum broadly 
conical, obliquely rostrate; spores .007 to .009 mm. 
On stones, rarely on the ground, in calciferous districts. New 
Jersey (Austin); Pennsylvania (James, Porter, Rau); Ohio (Sulli- 
vant); Canada (Macoun). 
Type locality American; collected by W. S. Sullivant, at Co- 
lumbus, Ohio. Type at Kew. in Herb. Schimper. 
ILtust. Sulliv. Icon. Musc. 153. p/. 98. 1864. 
Exsic. S. & L. Musc. Bor. Am. Ed. 1, no. 275; Ed. 2, no. 
408. Aust. Musc. App. no. 296. 
2. Tuurpium minutuLum (Hedw.) Br. & Sch. 
Thuidium minutulum Br. & Sch. Bryol. Eu. fasc. 49-51. 1852. 
Hypuum minutulum Hedw. Musc. frond. 4: 99. 1791. 
Plants small, dark green, in thin mats: stem 2 to 4 cm. long, 
creeping, pinnately branched ; branches simple or pinnate, spread- 
ing, subcompressed; paraphyllia semple, 3 to © cells long; stem 
leaves ovate-triangular, acuminate, recurved or revolute below, 
Margins papillate-crenulate, costa vanishing in the abrupt usually 
curved acumen; leaf-cells quadrate-hexagonal (.009 mm.) pluri- 
Papillate, marginal larger; branch-leaves ovate-acuminate, sub- 
crispate and appressed incurved when dry. Monoicous ;, perichetial 
bracts erect, long and narrowly acuminate, entire; pedicel long, 
flexuose; capsule oval-oblong to obovoid-oblong, asymetrical, hori- 
* Apical cell of ultimate branch leaves crowned with two or more papillae. 
