194. DIPLOPERISTOMI. . [Bryum. 



Bryum palustre. Swartz. Engl Bot. t. 391. Turn. Muse. Hib. 

 p. 113. Moug. et Nestl n. 135. Hook. Fl Scot. P. II. p. 149. 

 Hobson, Brit. Mosses, v. 1. n. 97. Drummond, Muse. Scot. v. \. n. 97. 

 Arn. Disp. Muse. p. 133. 



Mnium palustre. Linn. Sp. PI. p. 1574k Hedw. Sp. Muse. p. 

 188. Schwaegr. Suppl v. I. P. II. p. 122. Brid. Meth. p. 121. 

 Smith, Fl. Brit. p. 1346. 



Mnium polycephalum and inordinaturn. Brid. Meth. and M. reclina- 



tum. Schwaegr. Suppl. v. 1. P. II. p. 108 Dili Muse. t. 31. f. 3. 



HAB. Bogs. 



Stems from two to four inches long, much branched, and 

 frequently throwing out innovations. Leaves erecto-patent, 

 lanceolate, obtuse, the margins much recurved or revolute, 

 entire, or at most appearing but very indistinctly serrulate at 

 the point, under a high magnifying power ; the nerve reaching 

 almost to the point; the surface papillose. Male flowers, 

 according to Hedwig, and other authors, discoid. Those ter- 

 minal capitular bodies, which so much resemble the anthers of 

 B. androgynum, are considered gemmae, and arise not only 

 from the main stems but from the innovations, which become 

 gradually lengthened out, and are destitute of leaves. Capsules 

 ovate, oblique, sulcated, brown ; lid conical. 



Notwithstanding the close affinity between the present and 

 the preceding species, they have, by many authors, been placed 

 in different genera. In both, the leaves are of the same form 

 and texture, but the present species has them somewhat obtuse, 

 and, for the most part, entire ; when otherwise, (for they are 

 subject to vary,,) the similarity is very great. In the capsule 

 there is a further difference, and according to Hedwig, a more 

 important one in the capitula terminating the stems or branches ; 

 for while in one species, (B. androgynwn,) they are considered 

 to perform the office of anthers, in the other they can be only 

 looked upon as gemmae, the male flowers being discoid. The 

 structure of the inner peristome of this exactly resembles that 

 of the preceding species. 



We wonder at Mohr's describing the leaf of B. palustre as 

 subulate. Some of them, indeed, have the margins so revolute 

 as to appear at first sight almost linear. 



