62 



THE MOONWORT AND ITS ALLIES. 



matric aria folium that have grown in situations unsuited 

 to them. They would therefore seem more properly 

 named B. matricaricefolium tenebrosum. 



The smallest are only an inch high with tiny thread, 

 like stems and minute fertile and sterile parts, while the 

 larger sometimes reach a length of nine inches. They 

 can hardly be called nine inches high, since in such speci- 

 mens the stem is usually decumbent with two or three 

 inches of the stipe under ground. 



Like B. simplex, this form is ex- 

 tremely variable. In speaking of it at 

 the Boston Meeting of the Fern Chap- 

 ter in 1898, Mr. Eaton said: "The 

 average height above ground is two 

 inches and most commonly the sterile 

 lamina is sessile or slightly stalked, less 

 than one quarter of an inch long, the 

 edge inflexed and top bent down just 

 as it covered the fertile division. . . . 

 In this state the sterile division bears 

 one lobe or notch on each side and the 

 apex is emarginate. Often it bears a 

 ^i\ sporangium and may even bear one or 



f * two on each lobe. From this there 



may be found a regular series up to 

 the fully developed form, one and 

 three fourths of an inch long, of which 

 three fourths of an inch is petiole. 

 There are in this two or three pairs of 

 otrickiuin matron*, semi-lunate lobes, the lower of which 



folium tenebrosum. 



are alternate and all decurrent 



In small specimens the fertile division is overtopped by 

 the sterile, but in the larger plants, the sterile division 



