MOSSES WITH A HAND-LENS 



I 



' 



Fig. 35. Hypnum dilitatum X 3 ; leaves and capsule X 10. 



capsules are not beaked. They mature in July according to 

 Limpricht, but in autumn according to my observations. 



The Round-leaved Hypnum is frequent in mountain streams, 

 but has formerly been referred to another closely related species 

 {H. molle Dicks.), a much rarer moss with ovate-elliptical leaves. 



There are several other species of Hygro hypnum that may 

 be found in water. One of these (H. ochraceum Turn.) may be 

 recognized by its yellowish or ochre-green color and strongly 

 secund leaves. 



THE BRACHYTHECIUMS 



THE Brachytheciums, as previously stated (p. 36), are dis- 

 tinguished by their short thick unsymmetric cernuous cap- 

 sules, and leaves with a well developed midrib. There are 

 at least two species of Brachythecium that should be classed among 

 the water-loving members of the Hypnum Family, although they 

 are not so thoroughly aquatic as the two species just described. 



The Rivulet Brachythecium (B. rwulctre B. & S. ) loves best 

 the wet gravelly soil at the edges of cool swift brooks. Fre- 

 quently it will entirely cover the gravelly bottom of a mountain 

 stream that is nearly dry during the summer. It is submerged at 

 times of high water and never grows in places that become en- 

 tirely dry; occasionally it will grow submerged, but even then it 

 is attached to the gravel at the bottom of the stream and not to 

 the stones, as in the case of the two preceding species. When 



