GENERA AND SPECIES. 53 
PLATE XIII. 
ASPLENIUM. Linnezus. 
SPLEENWORT. 
GEN. CHAR.—Fruit-dots oblong or linear, oblique; indusium 
arising from the lateral veins, opening toward the mid-rib, sometimes 
double; veins free, simple, or forked. 
The genus Asplenium is the type of the tribe Aspleniez, 
and is one of the largest of the whole family of ferns. Ten 
species are indigenous to Kentucky, and embrace all the 
species found in the Northern United States, except the 
somewhat doubtful A. ebenoides. Their habitat is as 
varied as their forms. They are found on mountain sides 
or in moist, open woods, on shaded cliffs, or in deep, rich 
valleys; some are very small, scarcely more than three or 
four inches in height; others attain the height of as many 
feet. The common name of the genus is Spleenwort, from 
its fancied virtue in curing diseases of the spleen. 
The sori, or fruit-patches, are elongated or linear in form, 
arranged along the back of the frond somewhat obliquely 
to the mid-rib, and near the middle of the pinnule—never 
at its margin. In an examination of the Asplenium, the 
young student should procure a well-developed specimen, 
richly covered with fruit-patches; otherwise it will be diffi- 
cult to determine the different species, especially the exotic. 
The Plate will serve as a guide for all our native species; 
figure I represents pinne slightly magnified; figures 2 and 
3, sporange and spore greatly magnified (Hooker and 
Bauer); figure 4, trichome or root-hair. The drawings of 
figures 1 and 4 were furnished by Prof. Hussey. The tri- 
chome (fig. 4) is not generic in character, but is found in 
some species. 
