BOTANICAL EXCURSION TO NORTH CAROLINA. 87 
fluous. Near the cave we saw some trees of Zilia hetero- 
phylla, Vent. (ZT. alba, Michx. f.), and collected a few speci- 
mens with unopened flower-buds. It appears to be the most 
abundant species along the mountains. 
Our ride next day offered nothing of interest. Near 
Staunton, we saw some patches of Delphinium consolida, 
where it was pretty thoroughly naturalized in the time of 
Pursh. We did not observe Spirca lobata, which Michaux 
first met with in this vicinity, and which Pursh, as well as 
later botanists, found in various parts of the valley. Passing 
the town of Lexington in the evening, we arrived at the 
Natural Bridge towards morning, where we remained until 
Monday, and had an opportunity of botanizing for a short 
time before we left. On the rocks we found plenty of As- 
plenium Ruta-muraria, Sedum ternatum, and Draba ramo- 
sissima with ripe fruit. In the bottom of the ravine, directly 
under the stupendous natural arch (the point which affords 
the most impressive view of this vast chasm), we collected 
specimens of Heuchera villosa, Michx., in fine flower on the 
28th of June; although, in the higher mountains of North 
Carolina, where it also abounds, the flowers did not appear 
until near the end of July. This species is excellently de- 
scribed by Michaux, to whose account it is only necessary to 
add that the petals are very narrow, appearing like sterile fila- 
ments. Although a smaller plant than A. Americana, the 
leaves are larger, and vary considerably in the depths of the 
lobes. It is both the H. villosa and H. caulescens of Pursh, 
who probably derived the latter name from the strong elon- 
gated rhizoma, often projecting and appearing like a suf- 
frutescent stem, by which the plant is attached to the rocks ; 
since he does not describe the scape as leafy, nor is this at 
all the case in the original specimens. The H. caulescens of 
Torrey and Gray’s Flora with the synonym, must also be 
united with H. villosa, which in that work is chiefly described 
from specimens collected by Dr. Short in Kentucky, where 
everything seems to grow with extraordinary luxuriance. 
With these, the plant we collected entirely accords except 
that the leaves are mostly smaller, and more deeply lobed ; 
