76 PLANT LIFE OF ALABAMA. 
vations thus formed are called by the people of the country “ rock 
houses.” In these gloomy recesses, never visited by the direct rays 
of the sun, their roofs and walls constantly moistened by the water 
oozing from every crevice, some of the rarest and most delicate ferns 
find a shelter from wind and sudden changes of temperature. Zricho- 
manes petcrs/t, the tiniest of this order in the United States, and con- 
fined to northern Alabama, is at home in these rock houses, and thence 
it was first brought to light by Judge T. M. Peters, who discovered it 
on the banks of the head waters of Sipsey River. The filiform hor1- 
zontal rhizomes are interwoven into dense patches, their fronds of 
dark green scarcely an inch high, somewhat resembling the thallus of 
a large liverwort. This fern was subsequently found in a similar 
locality on the western edge of the table-land by Prof. E. A. Smith, 
and later by the writer on its eastern border at the falls of Black 
Creek, in Etowah County. Trichomanes radicans is also a frequent 
inhabitant of these rock houses, being found on wet, deeply shaded, 
rocky walls northward to the Cumberland Mountains of Kentucky. 
The long creeping rootstock of this beautiful fern, adhering firmly to 
the rock, decorates the roof and walls of these recesses. Asplendwm 
trichomanes, with its fronds of brightest green, ana the thallus of a 
large liverwort (Dumortiera sp.) are the frequent companions of the 
above. Of plants of higher orders only a few have been observed in 
these cavities. Thin grass (Agrostis perennans) with its weak, decum-. 
bent stems, occurs here, where its foliage is scarcely ever affected by 
frost and never touched by the direct sunlight, and Heuchera rugelii 
is also quite frequently found on the damp ledges which form the 
threshold of the caves, but rarely penetrates beyond them. 
LHydrophytic plant associations (paludial plants).—On the table-land 
beyond the channels of the large streams and their very numerous 
branches no areas of great extent of a water-soaked or submerged 
soil are found, and the narrow channels through which the water 
rushes toward the lowlands afford but little chance for the spread of 
a hydrophile vegetation. The wet grassy swales are inhabited by the 
following: 
Andropogon virginicus. Carex granularis. 
Homalocenchrus (Leersia) virginicus. Itteocharis tenuis. 
Panicularia nervata. Eleocharis acicularis.' 
Panicum rostratum. Eleocharis ovata} 
Panicum commutatum. Scirpus polyphyllus. 
Panicum polyanthes. Dichromena colorata. 
Panicum sphaerocarpon. Kobresia pumila. 
Carex lurida. Juncus marginatus. 
Carex lupulina. Juncus (common species) . 
Carex intumescens. Cicuta maculata.? 
Carex squarrosa (rare). Coreopsis tripteris.1 
Carex torta. Eupatorium maculatum.’ 
1 Occurs also in the Louisianian area. 
