Bog Plants 



351 



the surface have sphagnum for their filling, but they are 

 tough and pliant, like strips of felt, owing to the close 

 interlacing of roots and stems of the other plants of the 

 bog cover. 



Many delightful herbs grow on the surface of the bog. 

 The pitcher-plant shown in our figure is one, and the 



sundew (see fig. 172 on p. 

 283) is another carnivor- 

 ous species. These, as we 

 have seen in the preceding 

 chapter, have their own 

 way of getting nitrogen when 

 the available supply is small. 

 Orchids of several genera 

 (Habenaria, etc.) and moc- 

 casin flowers (fig. 208) there 

 bear beautiful flowers. Cot- 

 ton grass (Eriophorum) is 

 showy enough with its white 

 tufts held aloft when in 

 fruit, and a beaked rush 

 (Rynchospora) is its natural 

 associate. In places where 

 the surface rises in little 

 hummocks, there are apt to 

 be patches of the xerophytic 

 moss, Polytrichium, associ- 

 ated with charming little 

 colonies of wintergreen and 

 goldthread. At the rear 

 of the heath shown in our figure stand huckleberries and 

 bog brambles and masses of tall bog ferns while thickets 

 of alder and dogwood crowd farther back. 



Where sphagmmi borders on open water, there often 

 lies in front of it the usual zone of aquatics with floating 

 leaves, as shown in the accompanying picture, and in 



Fig. 208. A charming bog plant, 

 the moccasin flower. Cypri- 

 pediiim reginae). 



