120 BOTANICAL GAZETTE [repaow 
from 2000 to 3000 feet. Here an occasional specimen is found wi 
trunk twelve inches in diameter three feet above the ground, and ber 
ing a well formed top with wide spreading branches. 
The bark of the trunk and larger limbs is thick, rough, att 
entirely destitute of spines, the spines falling away with the out 
layers when the branches are about four inches in diameter. Itvaie 
in color from almost black to yellowish brown, depending upon ® 
thickness and age. The terminal joints are very succulent and alms 
devoid of woody tissue. They are easily detached and usually develj 
roots after falling to the ground, establishing themselves as indepttt 
ent plants.° The tubercles on a joint of the first season’s growth be , 
from five to fifteen loose-sheathed spines, but in common with may 
other species of cylindrical opuntias, several spines develop at th 
upper margin of each pulvinus during the season’s growth, s0 that 
tubercle on a stem several years old may bear as many as forty ore® 
sixty well developed spines. . : 
In Dr. Engelmann’s description and in the account of this pity 
as given by most writers the flowers are said to be purple. They a 
however, purple only when dried or withered. In fresh condition tf 
are bright pink. The plant of Lower California referred to this spect 
is said by Mrs. Brandegee to have yellow flowers.’ When fully oF 
the short petals are strongly reflexed. In Arizona this plant does 
bloom until July, and from this time flowers may be found until 
in September. The early flowers develop from the tubercles at 
ends of the joints of the previous year’s growth, while the later 
fruit. Ifa fruit not fully ripe be placed on moist sand, roots Will 
from the 
ee forming an independent plant without the growth ae 
within. Fruits attached directly to the stems are usually !atg"” 
° Vegetal dissemination in Opuntia, Bor. Gaz. 20: 356- 
” Notes on Cacteze, Erythea 5 : 122 
. 
