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Mnium sylvaticum Lindb. 



i, Plant natural size showing stolons; 2, apex of leaf enlarged to show the 

 serrate margin and cuspidate apex; 3, 4, 5 and 6, various shapes of 

 leaves; 7, mouth of capsule enlarged, showing annulus (a) and peris- 

 tome, including cilia of internal peristome (b). ( From Mrs. Britton's 

 Observe)- articles, by permission). 



There are as many species of Mnium in our range as of Dicra- 

 num, but the leaves are so large and usually so well characterized 

 by border or teeth that they can readily be determined without 

 the capsules. 



In determining Mniums the leaves should be first examined 

 under the compound microscope to determine whether or not they 

 have the borders of long narrow cells, illustrated in figure 2 and 

 in the glossary which appears in this issue. If the border be 

 present, is it entire, serrate with a single row of teeth, or with a 

 double row of teeth, z. e., with the teeth in pairs? If the margin 

 be present and the teeth be single and single-celled, and not pres- 

 ent much below the middle of the leaf, and also if the capsules be 

 single and the stolons present, you have the "Woodsy Mnium. 



If the plant was gathered on rocks or stones by the bed of a 

 brook and has very large stolons with large leaves, it may very 

 likely be the "toothed Mnium" (M. cuspid at um (L) Xeck. ), 

 usually known as M. affilne Bland. This species is distinguished 



