ATHYRIUM. 
121 
but all the various forms are plants of great delicacy and 
beauty. The fronds are of annual duration, varying in 
size from tufts of a few inches high, to plumy masses of 
the height of three or four feet; and the texture is thin, 
and almost transparent; on which account the nature of 
the venation, and of the connection of the parts of fructi¬ 
fication, may be here very well seen and studied. The 
genus serves to connect the Atpidktm-Y&a and the Asple- 
nium-WkQ groups of Ferns, being of intermediate character. 
It differs from the former in having the sori elongate 
instead of round. The sori, which form short lines, are 
sometimes curved at the end, or even horseshoe-shaped, 
and in age, being short, and often dilated, approaching the 
rounded form, the Lady Fern has, by many writers of 
discrimination, been placed in the old genus Aspidium; 
but if the fructification is examined while young, imme¬ 
diately before or after the indusium has burst, its true 
character will readily be seen. We have here an illus¬ 
tration of the inconvenience which arises from the 
preservation as herbarium specimens, only of such as have 
the fructification quite mature; for this, without doubt, 
was the cause of the Lady Fern having been referred to 
the family of Aspidium, with which it has no real 
