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\.—0n Bog Mosses. By B. Bkaithwaite, M.D., F.L.S. 



Plates XXXIX and XL. 



9. Sphagnum rigidum Scbimper. 



Torfmbose, p. G5, Tab. XVin. (1858). 



Plate XXXIX. 



Syn.— ScMmper Synop. p. G78 (1860). Lindberg Torfmos. No. 8 (1862). 

 Russow Torfm. p. 77 (18G5). Milde Bryol. Siles. p. 390 (1869). Sph. compactnm 

 /3 ri<]idnm Nees & Hnsch. Bry. Germ. I, p. 14, Tab. II, fig. 5* (1823). Bridel 

 Bry. Univ. I, p. 17 (1826). C. Miiller, Syn. I, p. 99 (1849). Sph. ambuiuum 

 Hubener Muse. Germ. p. 25 (1833). Sph. tristichum Scliultz in But. Zeit. (1826). 

 Sph. iminersum Nees & Hornsch. Bry. Germ. I, p. 11, Tab. II, fig. 4. Sph. strictum 

 Sulliv. Muse. Allegh. No. 201 (1845). 



Monoicous. Tufts dense, rigid when dry, glancous-green above, 

 ivhitish below ; stems erect, dark brown or blackish, 3-10 inch high, 

 densely ramulose, usually 2, sometimes 3 or 4-partite ; cortical cells 

 small, non-porose, in 2-3 strata. Branches 3-4 in a fascicle, short, 

 1-2 erecto-patent, obtuse, the others deflexed, slender, flagelliform, 

 lax-leaved, cortical cells longer, the porose scarcely distinct from the 

 rest. Cauline leaves minute, erect, inserted ohliquely, broadly ovate, 

 auricled, the apex rounded, erose ; areolation lax and rhomboidal in 

 the middle, with a broad border of thin, narrow cells, without fibres 

 or pores, or with a few fibres in the basal cells. Leaves of the 

 divergent branches quinquefarious, from an ascending base, erecto- 

 patent, rigid when dry, ovate-oblong, very concave, and somewhat 

 cucidlate at a])ex,but ivhen flattened out, more or less truncate and 

 denticulate, the margin inflexed ; hyaline cells confluent above and 

 below, wide, reticulose-fibred, with many unequal 2^ores, the mar- 

 ginal narrow, in two rows, the outermost of which has a longi- 

 tudinal furrow; chlorophyll cells compressed nearly central. 



EXPLANATION OF PLATE XXXIX. 



Sphagnum rigidum. 



a. — Plant of the typical form. 



1. — Part of stem with a branch fascicle. 



3. — Fruit and jjerichsetium. 4. — Bract from same. 



5_ — Stem leaves. 5a«. — Areolation of apex of same. 



6. — Leaves from middle of a divergent branch. 



6 a a. — Areolation of apex of same expanded. Qx. — Transverse section. Qp. — 



Point of same. Q c. — Cell from middle x 200. 6 r. — Reticulation at 



back X 400. 

 7. — Intermediate leaf from base of a divergent branch. 

 8. — Leaf from a pendent branch with an antheridium. 

 9 X. — Part of section of stem. 

 10. — Part of a branch denuded of leaves. 

 /3. — Var. compactuni. 

 y. — Var. squarrosum. 



