38 
from O. vulgaris, Dr. W. came at once, as soon as the mountain 
region and the pine woods commenced, on several beautiful and 
interesting members of this curious family, an evidence that he 
approached the favourite home of the Cactus tribe, Mexico. 
On Waggon-mound the (flowerless) specimens of a strange 
Opuntia were found, with an erect, ligneous stem, and cylindrical, 
horridly spinous, horizontal branches. The plant: was here only 
five feet high, but grows about Santa Fe to the height of eight 
or ten feet, and continues to be found as far as Chihuahua and 
Parras. In the latter more favourable climate it grows to be a 
tree of twenty or thirty, and perhaps forty feet high, as Dr. W. - 
informs me, and offers a beautiful aspect when covered with its 
large red flowers. It is evidently the plant which Torrey and 
James doubtfully, though incorrectly, refer to Cactus Bleo, H.B.K. 
It is nearly allied to Opuntia furiosa, Willd., but well distin- 
guished from it; and as it appears to be undescribed, I can give 
it no more appropriate name than O. ardorescens, the tree Cactus, 
or Foconoztle, as called by the Mexicans, according to Dr. Gregg. 
The stems of the dead plant present a most singular appearance ; 
the soft parts having rotted away, a net work of woody fibres 
remains, forming a hollow tube, with very regular rhombic 
meshes, which correspond with the tubercles of the living plant. 
The first Mammillaria was also met with on Waggon-mound, 
a species nearly related to MW. vivipara of the Missouri, and also 
to the Texan M. radiosa, (Engelm. in Plant. Lindh. inedit.,) but 
probably distinct from either. Mr. Fendler has collected the 
same species near Santa Fe. | 7 
On Wolf creek the curious and beautiful Fal/ugia paradoza, 
Endl., looking like a shrubby Gewm, was found in flower and 
fruit; also a (new ?) species of Sfreptanthus, and an interesting 
Geranium, which I named G.pentagynum, because of its having 
its five styles only slightly united at base, while most other 
— have them united for about two-thirds or more of their 
ength. 
In the prairies about Wolf creek, in an elevation of about 
6,000 and 7,000 feet, the sniallest of a tribe of Cactacee was 
detected, numerous species of which were discovered in the 
course of the journey south and south-east: several others have 
also been found in Texas. I mean those dwarfish Cerer, 
some of which have been described with the South American 
genus Lchinopsis, or have been referred alternately to Cereus or 
Lichinocactus, and which I propose to distinguish from all these + 
under the name of Hchinocereus, indicating their intermediate 
- position between Cereus and Hehinocactus: they approach more 
