THE ROCK SPLEENWORTS. 165 
broad base and graduated upward to the pinnatifid apex. 
The lower pinne are stalked and elongated-triangular in 
shape, with lanceolate and sharply toothed pinnules, as 
are also the pinnules near the tip of the frond. None of 
them appear to be decidedly wedge-shaped. The short 
sori are borne on most of the fronds and early become 
confluent over the under surface as in the wall rue. 
Occasionally the lower sori are double. Fronds ten 
inches long are reported from Kentucky, and Williamson 
is quoted as having collected a plant in that state hav- 
ing more than fifty fronds. 
The mountain spleenwort is found 
sparingly from Connecticut and New 
York to Georgia and Arkansas. It is 
an inhabitant of the precipices in 
mountainous regions and frequently 
grows in inaccessible niches. Lantern 
Hill in Connecticut, near the Rhode 
Island State line is its limit, northeast- 
ward so far as known. Writing of this 
station for it, in the Fern Bulletin, Dr. 
C. B. Graves says, “ Asplentum monta- 
num is able to maintain itself on the 
driest and most exposed cliffs provided 
there are holes and crevices which af- 
ford a holding place. In_ such sit- 
uations it is much stunted and incon- 
spicuous, the fronds sometimes fruiting Fertile frond of 
: : MOUNTAIN 
when less than half an inch in length. | sPLEENWORT. 
It reaches its best development on moist, shaded, over- 
hanging ledges.” This species usually chooses situations 
similar to those selected by the wall rue, and may be 
looked for wherever the latter is found. No doubt there 
