86 MISSOURI BOTANICAL GARDEN. 
leptocaulis. It has grown with us in cultivation at San ‘An- 
tonio, Texas, since March, 1908. The winter of 1910-11 was 
rather severe, and as a consequence much of each plant was 
killed. They, however, bloomed profusely in 1911. It blos- 
somed the second year from single joint cuttings. 
The type was collected at La Tule, Texas, March 5, 1908. 
The type specimen is a sheet consisting of a joint and flower 
number 9046, put up May 4, 1910, at San Antonio, Texas, 
from a cultivated plant grown from a cutting of the original 
collection bearing the same number. The description is a 
compilation of several sets of notes taken mainly from culti- 
vated plants—Plates 9, above, 16 and 17. 
EXPLANATION OF PLATES. 
Plates 1, 2.—Opuntia Bentonii, from type plant. 
Plate 3.—Opuntia Gregoriana, from type plant. Note fallen fruit. 
Plates 4, 5.—Opuntia incarnadilla, from type plants in cultivation. 
Plate 6.—Opuntia vexans, from the type in cultivation. 
Plate 7.—1, Opuntia vexans, two right-hand rows, the first three 
of the figures representing mature dried fruits. 2, O. arborescens, 
left-hand row, the first of the figures representing a mature dried 
fruit. 
Plate 8.—Opuntia demissa, from native type plant. 
Plate 9.—1, Opuntia gilvoalba, above. 2, O. cyanella, below. 
Both under cultivation. 
Plate 10.—Opuntia cyanella. 
Plate 11.—1, Opuntia tardospina, above. 2, O. undulata, below. 
Both under cultivation. 
Plate 12.—Opuntia undulata. 
Plate 13.—Opuntia perrita: above, under cultivation; below, spon- 
taneous. 
Plate 14.—Opuntia perrita. 
Plate 15.—Opuntta tardospina, from a cultivated plant. 
Plates 16, 17,—Opuntia gilvoalba. 
