254 THE SENSITIVE AND OSTRICH FERNS. 
while it forms a more or less continuous border to all our 
streams and ponds. Very few of those who pass it or 
wade through it have any idea that it is a fern, for its 
broad coarse fronds are far from the common conception 
of fern leaves. 
The rootstock is as thick as a pencil and creeps just at 
the surface of the earth, frequently branching. In addi- 
tion to the fronds, it produces, here and there, append- 
ages exactly like the bases of the stipes but which end in 
a point and never become more than two or three inches 
long. The fronds are produced all summer but the 
young crosiers are most noticeable early in the year when 
they push up in such numbers in all low grounds as to 
make their tawny pink hue the prevailing one for some 
days. Seen in the mass, the young fronds can scarcely be 
calied beautiful, but a single one taken just as the pin- 
nules are unrolling and viewed from base to apex in the 
plane of the blade will show such a succession of scrolls 
and arches as to suggest a miniature of the interior 
of some old cathedral. 
When the sterile fronds are fully spread they are, to 
most eyes, coarse and ugly. They are ovate in outline, 
pinnate below and pinnatifid toward the apex. The 
pinnules are linear-lanceolate, the upper nearly entire, 
the lower sinuate-toothed or lobed. The fronds are 
borne on long stipes and often reach a height of more 
than two feet. About midsummer the fertile fronds ap- 
pear. They are shorter than the sterile, bipinnate, and the 
pinnules resemble rows of little green berries strung along 
the midribs. Many suppose each berry to bea sort of 
sporecase like those of the rattlesnake fern, but it is 
easy to see that they are simply closcly rolled pinnules 
enclosing the sori. Each sorus has an indusium but it 
