HYPNEI. 121 



68. H. commutatum, Hedw. ; dioicous ; stem dichotomous, 

 mostly prostrate ; branches pinnate, downy, leaves circinato- 

 secund, rather distant, ovato-lanceolate, striate, acuminate 

 slightly serrate; nerve very strong, reaching nearly to the 

 apex ; sporangium subcylindrical, curved, cernuous ; lid coni- 

 cal, acute. Hook. $ mis. t. xxvii.; Eng. Bot. t. 1569, 2250 

 in part; (Plate 10, fig. 5) ; Moug. Nest. n. 523. 



Tn watery places, especially where the soil is calcareous. 

 Bearing fruit in spring. 



Forming green or yellow-green tufts of various length. 

 Stem erect or procumbent, clothed with rufous down ; branches 

 pinnate ; leaves rather distant, but sometimes closer, falcate, 

 secund, broad at the base, ovato-lanceolate, slightly toothed, 

 silicate, twisted when dry ; nerve pale, strong, reaching nearly 

 to the tip ; cells very narrow, except at the angles ; perichsetial 

 leaves sulcate, strongly nerved; fruitstalk an inch or more 

 long, even, red ; sporangium oblong, curved, cernuous ; lid 

 conical, with a sharp apex. 



Differs from H. filicinum in the plicate leaves, which are not 

 so broad at the base, twisted when dry, and the narrower cells. 



In calcareous water, as, for example, in Northamptonshire, 

 it is frequently incrusted below with carbonate of lime, the 

 tips of the branches alone being free. 



69. H. filicinum, L. ; dioicous ; stem ascending, at length 

 villous; branches more or less pinnate; leaves spreading, fal- 

 cato-secund, ovate or ovato-lanceolate, even, acuminate, ser- 

 rated ; nerve reaching nearly to the apex ; sporangium oblong, 

 slightly curved, cernuous ; lid conical. Hook. Wils. t. xxvi. ; 

 Eng. Bot. t. 1570, 2126. ; (Plate 10, fig. 6) ; Moug. $ Nest, 

 n. 228. 



In watery places, especially in subalpine districts. Bearing 

 fruit in spring. 



