1m. 



FIG. 31. The Brake (Ptt'ris aquilina), showing part of the underground stem and two 

 leaves, one, (I 1 ), of the present year, in full development; the other, (/ 2 ), of the past year, 

 dead and withered, a.h, apical bud at the extremity of a branch which bears the 

 stumps of leaves of preceding years and numerous roots; Z 1 , mature active leaf; / 2 , dead 

 leaf of preceding year; hn, lamina of leaf; p, pinna; rh, portion of main rhizome; x, 

 younger pinna, which is shown enlarged at B. This pinna is nearly similar to the pin 

 nules of older pinnae. (X J.) 



