Fork-Mosses 



The leaves have a slender apex with a vein usually broad and 

 extending into the apex. The character of the vein and the cell- 

 structure are relied upon for perfect classification of the species. 

 The cells vary from short to linear oblong in the upper part of th e 

 leaf, to long and narrow in the lower part ; four-sided, inflated, 

 orange or brown, in the angles of the base. The leaves at the 

 base of the pedicel are sheathing and abruptly pointed. The 

 spore-cases are erect or turned to one side, the base, which is 

 often swollen so as to be unsymmetrical, tapers to an erect 

 pedicel, long and smooth. An annulus 

 is generally present. The lid is conical 

 with a long beak. The perisiome is sin- 

 gle, of sixteen teeth, two-cleft to the 

 middle and red-brown at the base. 



D. scoparium. 

 Perichaet ial 

 leaf. 



D. subidatum. 



D. congestum. 



D.scoparium. Leaf. 



The name of the genus is derived from a Greek word. 

 o?, a flesh-hook or fork, from a supposed resemblance of 

 its teeth to that instrument. The American Indians call Fork- 

 mosses "Women's heads," "because when you trample them 

 under foot they spring right up again." 



Although at first glance the Dicranums appear to have their 

 spore-cases on the sides of the plants, they truly belong to the 

 group of mosses which bears them on the summits of the 

 stems (acrocarpi) and not to the group which bears them on 

 the sides of the stems (pleurocarpi), for a closer examination 

 shows that a side stem grows on after the spore-case has 



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