Ji^ 



MUSCINE.E. 



admirably described. Since these two genera belong to very different sections, the 

 results obtained in this case may be considered as of general application to the 

 whole class. They agree in the fact that the mother-cell (which is at the same time 

 the apical cell) of a branch originates beneath a leaf from the same segment as the 

 leaf (Fig. io6, p. 132). In Fontinalis the branch arises beneath the median hne 

 of the leaf; but in Sphagnum beneath its cathodal half. In consequence of the 

 further development of the mother-shoot, the lateral shoot in Sphagnum appears at 

 a later period to stand by the side of the margin of an older leaf; and this is 

 probably the explanation of the earlier statement of Mettenius that in Neckera 



Fig. 229,— .-^ young plant of a Barbula in with the root-hairs h, to the growing ends of which particles of earth have 

 become attached ; at / a superficial root-hair is putting out branches containing chlorophyll, in other words a pro- 

 tonema ; at -^ a tuberous bud is growing from an underground branch of the root-hairs ; B this bud more strongly mag- 

 nified (^X2o; ^X30o). 



complanata, Hypmnn triquetrum^ Racomitrium canescens, and others, the lateral shoots 

 stand by the side of the margins of the leaves. When the shoot arises beneath 

 the median line of a leaf, and the leaves are arranged in straight rows, the further 

 growth of the stem may cause it to seem as if the shoot originated above the 

 median line of an older leaf, in other words as if it were axillary. Leitgeb states 

 that articulated hairs arise in the genera named in the axils of the leaves, or perhaps 

 more correctly at the base of the upper surface of the leaves. 



The dimensions attained by the leaf-bearing axes and axial systems of Mosses 

 show a wide range. In the Phascaceae, Buxbaumia, and others, the simple stem 



