30 FERN FAMILY 



rence is doubtful. It is known by the narrower, lanceolate 

 frond and somewhat wedge-shaped segments. 



5. PTERIS. Brake. Bracken. 

 1. P. aquilina L. Common Brake. Rootstocks widely 



creeping. Stalks 

 scattered, erect, 

 rigid, straw-color 

 or reddish brown, 

 a foot or more 

 high. Fronds 2 to 

 5 ft. long and as 

 wide at the base 

 (frequently attain- 

 ing a greater size), 

 triangular-ovate in 

 outline, hairy on 

 under surface, 2 to 

 4-pinnate, lowest 

 pinnae very large, 

 rapidly becoming 

 smaller and less 

 divided above, 

 edges of the segments entire. Sori on a continuous marginal 

 receptacle and covered by the continuous double indusium. 

 (Ptcridium aquilinum Kuhn.) 



The Common Brake is found in many parts of the world. 

 It is well known in the Sierra Nevada, where the creeping 

 habit of its rootstock often causes whole hillsides and valley 

 bottoms to be densely covered by the broad fronds, but it is 

 absent from high altitudes. Our West American form (var. 

 lanuginosa Bong.) differs from the eastern form in its greater 

 size and in having silky hairs on the under surface of the frond. 

 The spores do not usually develop until late July or August. 

 Much use is made of this fern by the Indians who use the 

 rootstocks for food and also in basketry. 



6. CHEILANTHES. Lip-fern. 

 Small ferns with the fronds divided 2 to 4 times into small 

 segments and the under surface covered with scales, wool, 

 or powder, except in C. californica. Sori borne toward or at 

 the ends of free veins, small and roundish at first, afterward 

 forming a nearly continuous marginal line, covered by a more 

 or less continuous indusium formed of the reflexed margin of 

 the lobes or whole segments. Stalks dark-brown and shiny. 



