Analytic Keys to the Species of Mosses. 
45 
Annulus present. 
Cells of leaf base elongated (1:4 to 1: 8) . . G. Donniana, 19. 
Cells of leaf base short (1:2) . . . . G. alpestris, 27. 
Grimmia Mannioe , apparently of this section, is described by Muller ( Flora 
1887, 228), from California. Mrs. E. G. Britton is of opinion that it is only 
G. alpestris Schleich. 
RHACOMITRIUM, p. 147. 
I. Branches fastigiate. 
Leaves with a short hyaline point R. Slide ticum, 5. 
Leaves muticous. 
N 
Costa with 2-4 lamellse at back.R. patens, 1. 
Costa not lamellose. 
Leaves with large quadrate cells at the basal angles, 
decurrent.R. depression, 8. 
Leaves not auricled nor decurrent. 
Obtuse. 
Perichsetial leaves costate, seta long . R. aciculare, 2. 
Pericheetial leaves ecostate, seta short . . R. Nevii, 4. 
Acute. R. Macounii, \ 
II. Branches fasciculate. 
A. Leaves muticous. 
Cells elongated above..R. fascicnlare, 7. 
Cells quadratic above.R. variuin, 8. 1 2 
[R. canescens may be sought here.] 
B. Leaves with a hyaline point. 
Cells linear throughout lamina . . . . R. niicrocarpum, 9. 
Cells quadratic above. 
Strongly papillose both sides.R. canescens, 11. 
Smooth (except at the point). 
Hyaline point denticulate .... R. heterostickuni, 6. 
[R. canescens var. lntescens and R. varium may be sought here.] 
Hyaline point strongly erose-serrate and papillose R. laniiginosuni, 10.. 
1 Kindberg: Bull. Torr. Bot. Club , xvi (1889), 93. 
2 R. Oreganum Renauld and Cardot: Bot. Gaz., xiii (1888), 198, pi. XV, is this species 
([fide J. Cardot in litt.'), which seems to be R. canescens , var. lutescens L. and J.; fide 
Mrs. E. G. Britton in lift. 
