96 ROSA MONTEZUM. 
53. ROSA Montezume. 
R. ramis inermibus. 
R. Montezumze Humb. et Bonpl. nov. gen. & sp. tom. 3. 
ined. Redout. ros. 1. 55. ft. 16. 
Hab. in jugo montium Mexicz sub gradu 19° latitudinis 
septentrionalis, altitudine plusquam 9300 pedum, 
in cacumine Cerro-Ventoso juxta S. Petri fodinam, 
(H. & B 
Unarmed, with smooth branches. Stipules fringed 
with glands; petioles downy, armed with many little 
prickles ; leaflets 5, oval, acute, naked on both sides, 
dark green above, paler beneath. Flowers pale red, 
solitary, without bractece, sweetscented; peduncle and 
elliptical tube of the calyx naked; sepals compound, 
dilated at the end. Redout. 1. c. 
So incomplete is the account given in Redouté’s 
work of this most interesting plant, that it is quite im- 
practicable to ascertain with certainty, even the division 
in which it should be arranged. The figure is probably 
taken from a dried specimen and is very like R. rubigi- 
nosa; yet the leaves are described as naked on both 
sides. If it be really an unarmed species, it will be 
easy to characterize it; but if, as I believe, it is only 
an unarmed branch that is figured, and if it do not be- 
long to this division, it must be placed in the next; 
but then I do not perceive how it is to be distinguished 
from R. canina. The petioles are said to be prickly, and 
I know no instance of a species without prickles on the 
branches, producing them on any other part. 
It was found on the chain of porphyry mountains 
which bound the valley of Mexico on the north, at the 
elevation of 1460 toises, on the top of Cerro Ventoso 
near the mine of San Pedro. The thermometer in 
May from 10° to 11° of Reaumur. 
