BnAUTIFUL FERNS. 
77 
under a microscope, when the grains will be presently seen 
to turn blue, the recognized sign of starch. This abundance 
of nutritive material in the root-stock enables it to send up 
a fine circle of large fronds in the proper season of the year. 
The stalks are from nine to fifteen inches long, rather 
stout, green when living, but straw-color when dried for the 
herbarium, in which condition they are furrowed in front and 
along the two sides. At the base they are covered with large 
ovate-acuminate brown or sometimes dark and shining scales. 
Mixed in with these are smaller and narrower chaffy scales, 
which also are found along the whole length of the stalk 
and the rachis. The cross-section of the stalk shows two 
rather large roundish fibro-vascular bundles on the anterior 
side, and three, the middle one largest, at the back. 
Several fronds are usually seen growing from a root- 
stock, those produced early in the season commonly sterile, 
and shorter than the others. The full-grown and fertile fronds 
are often two feet or two and a half feet long, and about 
one foot broad. The general outline is oblong-ovate, the low- 
est pinnae being scarcely, if at all, shorter than those in the 
middle of the frond. There are usually about eight or ten 
full-sized pinnae each side of the rachis, besides the gradually 
diminishing pinnae near the acute pinnatifid apex. The larger 
pinnae are from five to eight inches long, the middle ones an 
inch or an inch and a half wide, but the lowest ones two 
inches and a half broad. The greatest breadth of the pinnae 
is usually near the middle or even a little above the middle. 
