ILLUSTRATED STUDIES IN THE GENUS OPUNTIA.—IV. 27 
The type was prepared at Chico, California, September 9, 
1911, from cultivated specimens collected near El Paso, 
Texas, July 29, 1905. Both the type specimen and the origi- 
nal collection bear my serial number 8020. Two generations 
of this have been grown by vegetative propagation since its 
collection.—Plate 3. 
Opuntia incarnadilla, sp. nov. 
An erect, compactly-branched, arborescent species with a distinct 
cylindrical trunk 20 to 80 cm. in diameter, 2 to 3 or 4 meters or more 
high; joints of a striking blue-green with some bloom in the fall but 
much brighter in color in the spring, uniformly and regularly obovate, 
about 151% by 2814 em., smooth, flat, broadly rounded above and 
tapering uniformly below; areoles oval to obovate, 2 to 4 mm. long, 
enlarging in age to about 6 mm. in diameter, the lower usually 
unarmed and about 2cm. apart; wool brown turning gray to dirty 
black; spicules yellow, very inconspicuous even on old joints when 
they are slightly darkened, scarcely visible up to 18 months old; 
spines white with translucent bonelike tips, short, stout, erect or when 
young bonelike throughout, bent, twisted, flattened, erect or recurved, 
irregularly distributed, commonly none below, 1 to 2 above and 2 to 4 
on edges of the joints, with an occasional joint with entire side armed 
with 1 to 4, seldom 2 cm. long and from that down to 8 mm., increasing 
with age on old stems both in length and numbers; fruit bright deep 
red all through, palatable, oval to subglobose with comparatively 
large areoles filled with prominent brown wool, a few inconspicuous 
spicules in the center and 5 or 6 fugacious, delicate spines below 
which are commonly 6 to 8 mm. long. 
The species is characterized by its beautiful blue-green 
color, uniformity of joint outline, and habit especially. It 
should be placed with the mansa or large cultivated Mexican 
species. In California it has made a growth of four feet high 
by about the same measurement in spread of branch, in four 
years, and produced a few fruits the third season and a small 
crop the fourth. At Brownsville, Texas, it is perfectly hardy 
but does not grow as well, and has not yet produced any fruit, 
although the plants are the same age as those at Chico, Cali- 
fornia. The spicules are much more numerous at Browns- 
ville. 
The type specimen bears my serial number 8074 and was 
prepared from cultivated specimens at Chico, California, Sep- 
