THE ROCK SPLEENWORTS. 
nooks on dry cliffs and often grows luxuriantly 
in the smallest crevices. In comparison with 
many of its allies it may be called common and 
next to A. Trichomanes is the spleenwort oftenest 
found on cliffs. 
The fronds grow in tufts from a short rootstalk 
and are seldom more than five inches long, while 
fruiting specimens only an inch high are not rare. 
In shape, they vary from ovate to oblong-ovate 
and are twice pinnate with stalked pinne and 
pinnules. The pinnae are shaped like the 
frond, and the pinnules are ovate, obovate 
or fan shaped with the outer margin slightly 
toothed. Occasionally the pinnules are 
lobed or again pinnate. In texture the 
fronds are thick and leathery and they en- 
dure the winter without injury. Several sori 
are borne on each pinnule and nearly every 
frond is fertile. The indusium soon withers 
and the sori become confluent over nearly all 
the under surface. 
Small as this species is, it does not lack for 
common names. Among them, wall rue and 
stone fern are in allusion to its place of growth, 
and white maidenhair from its being confused 
with the maidenhair spleenwort. Its old name 
of tent-wort was originally taint-wort and was 
given because the plant was supposed to be a 
specific for a scrofulous disease called “ the taint.” 
The fronds were once considered good for coughs 
and for diseases of the liver and spleen, but their 
use for such things has now been abandoned. 
The rue spleenwort is found from Vermont, 
THE WALL RUE. 
Asplenium ruta-muraria, Three forms of fronds. 
