Botanical Excursion to the Mountains of North Carolina. 15 



pretty thoroughly naturahzed in the time of Pursh. We did not 

 observe SpircBa lobata, which Michaux first met with in this vi- 

 cinity, and which Pursh, as well as later botanists, found in vari- 

 ous 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 Aspleniuni Ruta-muraria, JSedum ternatum, 

 and Draba ramosissima 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 described by 

 Michaux, to whose account it is only necessary to add, that the 

 petals are very narrow, appearing like sterile filaments. Although 

 a smaller plant than H. 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 elongated rhizoma, often projecting 

 and appearing like a suflTrutescent 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 a. of Torrey and Gray's Flora,* with the syno- 

 nym, must also be united with H. villosa, which in that work is 

 chiefly described from specimens collected by Dr. Short in Ken- 

 tucky, where every thing seems to grow with extraordinary lux- 



* The specimen from Mr. Curtis, the only one from the mountains of North 

 Carolina which these authors had before them, and which they correctly enough 

 considered as the H. caulescens of Pursh, is in too advanced a state, nndhad lost 

 from age most of the shaggy rusty hairs which so copiously clothe the petioles and 

 lower part of the scape ; and the leaves being smaller and more sharply lobed, it 

 was not recognized as the same species with the luxuriant Kentucky plant; but 

 was partly confounded with a different and larger-flowered species, the H. cau- 

 lescens p. Torr. 8^ Gray, I. c. from Buncombe county. The latter (H. Curtisii, 

 Torr. Sf Gray, ined.) has flowers quite as large of those of H. Americana, spat- 

 ulate-lanceolate petals (apparently purple) which scarcely exceed the lobes of the 

 calyx ; and the filaments, which are less exserted than the styles, are pubescent un- 

 der a lens. The aid of its discoverer, however, is needed to complete the character 

 of this species, the radical leaves being imperfect in our solitary specimen, and the 

 cauline pair which it presents may very probably not be of usual occurrence. 



