a 
22 BOTANICAL GAZETTE [ FEBRUARY 
The short, brownish spines have inconspicuous sheaths and ya 
in number from four to fourteen on young joints, while on olderstem 
there may be as many as twenty-five to a single tubercle. The floves 
appear in May, expanding to nearly an inch and a half in diameter 
the comparatively narrow petals varying in color from greenish-red! 
greenish-yellow. 
The fruit ripens from December to February, usually withering al 
drying on the tree. Sometimes it does not dry but remains fleshy, 
adhering to the branches until late the next summer or in soit 
instances for longer than two years. At maturity it frequently split 
open, showing the many angular seeds within. It 1s not ‘unusual fo 
fruits that remain to become proliferous the second season. It varie 
remarkably in size and shape, but is usually pear-shaped and from 0 
to two inches in length. A form of this plant growing on the foot 
hills of the Santa Catalina mountains bears fruit less than three-foutll 
usually growing from them are one to three reflexed, persistent spin 
Considerable confusion exists regarding the geographical ‘i 
tion and specific characters which separate O. Whipplet Engel 
arborescens Engelm., and O. spinosior (Engelm.), the latter a = 
mediate species heretofore considered as a variety of O. Whipp! 
Whipplet is a species of the Colorado plateau,” growing at an el 
of from 5000 to 7000 feet. As I understand this species 1 have 
found it growing south of this plateau. In Dr. Engelmanns * 
of this plant,” under the brief description of the variety we aré™ 
for illustration to pl. 17, figs. 1-4. Turning to this plate the 7 
indicated are marked 0. Whipplet. The illustration is a0 exce™ 
representation of the plant of the Colorado plateau and se 
yeaa y represents the species instead of the variety. In the. 
yen of the species we are referred to pl. 17, figs. 56 and pl. 17 Bt 
J ¥eniog to these plates we find the figures marked QO. 47%" 
bei again there is confusion, but by comparing the plant of $0 
Arizona with these illustrations I conclude that they were mab” 
*°Garden and Forest g: 2. 11 Pacific R. Re Report 435" 
