1898]. BRIEFER ARTICLES 123 
material collected here and really represent what has been known as 
O. Whipplet spinosior Engelm. 
O. Whipplei is a low, spreading bush, never arborescent and rarely 
more than two or three feet in height. The joints are usually some- 
what clavate,.and the spines are covered with white, glistening, loose 
sheaths, which gives the plant a characteristic appearance and readily 
separates it from related species. The flowers are not red as stated by 
Dr. Engelmann and followed by Dr. Coulter in his preliminary revis- ; 
ion, but a yellowish-green, and when fully expanded barely an inch in 
diameter. From the original account of the species and variety I infer 
the description of the flower was drawn from material collected by A. 
Schott south of the Gila river, and represents the plant designated as 
the variety spinosior, which has much larger purple flowers. The fruit 
of O. Whipplet is hemispherical and less than an inch in diameter. It 
a during the winter months and usually shrivels and dries on the 
plant, 
O. spinosior is not only specifically distinct from O. Whipplet, but 
fas a well marked variety in southern Arizona, viz., O. spinosior 
Senn. This southern species and variety are low growing trees 
re spreading tops. By most writers the species has been confused 
Ms O. arborescens. In my account of OQ. arborescens” the plant 
ilustrated is really O. spinosior, while the form with smaller flowers 
having fewer and narrower petals varying in color from red to yellow 
is the above variety. 
0. oo and fruit of O. spinosior are practically the same as in 
bigh sis ee the two species are readily separated by the long, 
bie ce rh of O. arborescens when compared with the short 
much small mullate ones of the former species. ‘The latter species is a 
al’er and more eastern plant, never approaching a tree in size, 
Ban ‘i _ United States. I have measured specimens of 
- alittle over i oreuy of Tucson with trunk two feet from the ground 
On the a inches in diameter. The plant grows with O. fulgida 
taken by O oT reaching the foothills, where i eee . 
ate covere Bis aks iH The eae and larger limbs ee a si 4 
The flowers a SNES renee, dark-brown bark in e ongate ges. 
the following ¥; arin April ae May, and the fleshy fruit ripens during 
T Magenta aed and spring. The large, conspicuous, deep-purple 
. ers, like all other species of this section known to me, 
Garden and Forest 9:2. 
