62 THE MOONWORT AND ITS ALLIES. 
matricariefolium that have grown in situations unsuited 
to them. Ilhey would therefore seem more properly 
named &. mutricariefolium tenebrosum. 
The smallest are only an inch high with tiny 
threadlike 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 
specimens the stem is usually decumbent with two or 
three inches of the stipe under ground. 
Like B. sampler, 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 av- 
erage 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 divison. . 
In this state the sterile division bears 
one lobe or notch on each side and the 
apex isemarginate. Often it bears a 
sporangium and may even bear one or 
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 
Botrychium matricarie. semi-lunate lobes, the lower of which 
Joie unirom®: see alternate and all decurrent. « 
In small specimens the fertile division is overtopped by 
the sterile, but in the larger plants, the sterile division 
