THE LADY FERN. 3 
The fructification of Athyrium will be found to consist of sori 
varying in form, and hence all parts of the frond should be tho- 
roughly examined. "Towards the extremities, that is to say, near the 
apices of the pinnules or segments, the sori will generally be found 
to consist of short lines, in which the characteristic curve is very 
little or not at all apparent. Such sori are undoubtedly asplenioid, 
and indieate the actual relationship of the genus. Next to these 
occur others which Professor Mettenius calls hamate, and which in 
their less developed condition answer to the semi-lunate sori which 
have been generally ascribed to Athyrium. These curved or 
hamate sori are formed by the receptacle, which constantly occupies 
the anterior side of the vein, crossing atthe upper end and returning 
more or less on the opposite or posterior side. When the receptacle 
only just crosses the vein, the result is that the back of the sorus 
becomes concave, and the slightly curved or semi-lunate sorus is 
produced. When it returns on the posterior side, to about one-fourth 
or one-half the length of the sorus on the anterior side, the hamate 
or hook-like sorus is formed. In addition to these forms of sori, 
in all the more divided forms of the species others occur at the 
base of the segments which are hippocrepiform or horse-shoe-like in 
figure. These are produced by the receptacle becoming shortened 
and more completely returned, so that the portions on the anterior 
and posterior sides of the vein are nearly or quite equal. The 
occurrence of these hamate and hippoerepiform sori, more or 
less numerous, is abundantly distinctive, amd absolutely separates 
Athyrium from. Asplenium, by a manifest tendency towards the 
structure of the Aspidieœ as represented in Lastrea. 
According to Mr. Newman, * the genus of the Lady Fern has 
always been a source of trouble and confusion to our botanists. 
“Lightfoot, Hudson, Withering, and Bolton," he remarks, “make 
it a Polypodium; Smith an Aspidium ; Hooker an Asplenium ; 
Babington an Athyrium; and all, as I conceive, with equal pro- 
priety. Filie-femina may readily be distinguished by its elongate 
and somewhat sausage-shaped clusters of capsules, covered by a 
similar-shaped involuere with its fringed free margin ; the attach- 
ment of the clusters describes. a concave, rather than a direct line as 
^* Newman, Hist. Brit. Ferns, 3 ed. 208. 
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