1900 | MOSSES OF NORTH AMERICA 13 
Missouri: Benton county, on moist rocks along Indian creek (C. H. 
Demetrio, 1893). Minnesota: Lewiston cave (J. M. Holzinger, 1889), Bear 
creek (J. M. Holzinger, 1890). Wisconsin: Madison (L. S. Cheney, 1892. 
Ren. & Card. Musci Am. seft. exsicc. no. 269). 
This form shows contrary variations to the preceding: the leaves are 
smaller, the cells quadrate, papillose; besides, the stem and the nerve are 
generally covered with high papillae. 
HyYMENOSTOMUM MICROSTOMUM R. Brown, Trans. Linn. Soc. 
12:572 (Gymnostomum microstomum Hedw., Musc. frond. 3: 71, 
pl. 308). 
According to Lesquereux and James, Manual 56, this species is not 
known from North America, and all the specimens that have been communi- 
cated under the generic name Aymenostomum are to be referred to the 
Weisia viridula var. gymnostomoides C, Mill. Yet the no. 54 of Sullivant 
and Lesquereux J/uscz Bor. Am. belongs undoubtedly to the Hymenostomum 
microstomum R. Br., at least in our set. 
Quite inseparable from Wezsta viriduda as to the vegetative organs, and 
differing only by the capsule closed with a membrane finally perforated in 
the center 
Weista Wimmeriana BS., Bryol. Eu. 33-36: 4, pl. 7. (Gym- 
nostomum Wimmerianum Sendtn. in Flora 23':59. 1840. Ayme- 
nostomum murale Spr. Musc. Pyr. no. 236. Gymnostomum murale 
Sch. Syn. 37. 1860. [ Ed. 1.]) 
Minnesota: Taylor's Falls (J. M. Holzinger, 1895). 
Resembling the slender forms of W. viridu/a in size, habit, shape, and 
areolation of the leaves; distinct chiefly by the inflorescence, which is paroi- 
cous, or sometimes, as in our Minnesota specimens, synoicous. The peri- 
stome is generally rudimentary; in our American specimens, however, the 
teeth are rather perfect, with 4-5 articulations. 
DIcHODONTIUM Oxympicum Ren. & Card., Rev. Bryol. 19: 74. 
1892.— Dioicum, humile, caespitosum, obscure viride. Caulis 
gracilis, erectus, 5—7™™ altus. Folia madida patentia subrecurva, 
sicca laxe erecto-flexuosa, apice incurvata, 1.50-1.75™™ longa, 
0.6™™" lata, e basi ovata vel oblonga paulo latiore breviter lingu- 
lata, obtusa subobtusave, subundulata, marginibus plana, cellulis 
prominulis minute crenulata, supra basin integram distincte den- 
ticulata, costa valida percurrente vel subpercurrente; cellulae 
