CONTRIBUTIONS TO WBSFERN BOTANY 123 
O, leptocanlis Eng. is an insignficant bush along the Colora- 
do river where the red and globular fruit, often ce ie like swel- 
lings in be trunk when proliferous are notice 
mosissima Eng, is an openly branched ast, like the 
last ney growing in the brush also but has very spiny fruit on the 
ends of twigs, but the vestiges of tubercies pi together like pave- 
met Cc 
Q. Bigelovii Eng., the horrid cholla, pronounced ites i8 a- 
bundant at about 1009 ft alt. from Whitewater to Arizo The 
erect stems are stout and 4-8 ft. high and with clusters at short 
and thick branches which fall off when brushed by stock and also 
adiere to the lega the more they try to kick them off. The fruit 
is yellow and mostly insect- stung, seldom maturing, and then 
with few seeds in an acid cavity, seeds white, borderless, 3-5 mm. 
wide, 1.5 mm. thick, round, sharply apiculate at raphe. This 
has the same disarticulating habit as O. cholla, prolifera, and ful- 
gida have and are shunned by all animals but the cactus wren and 
mockingbird thrush which nest in its branches. Fruit very epiny 
when young and becoming smooth in age. 
Q. echinocarpa Eng. This iserect and 2-3 ft, high, with 
fruit spiny around the top, and maturing the season of blooming 
and much eaten by chipmunks so that seeds are bard to find, It 
abounds hen Bigelovii and east to Utah. 
prolifera "En This seacoast cholla is erect and widely 
spreading with scattered branches, and fruit often producing buds 
which become floweres and these again proliferating into a string 
ted seed in the aborted fruit. This is a pestiferous plant. 
O. serpentina Eng. This rare coast cactus from San Diego 
is the only really prostrate species of the group and has very 
8 piny Bde and red or reddi 
vata Eng. This is the only dete wegen without 
sheaths “a the only one growing in dense patches with short 
and hooked stems decumbent and rooting below, flowers yellow, 
fruit 2 inches long, with white woo] and many § spicules. Seeds 
about 8 mm.wide. Abundant at Searchlight, and in the Moe- 
ave tes bere east pie i vas 
The fruit of this is spiny to 
he branches are a foot or 
more long and greenish- brown, with “the reddish flowers at the 
; Tropical in habit, as is Bigelovii 
0. Parryi a rig fis abounds on the humid western slope 
it ang except for a few spines at 
very tip. The fruits are muc ch eaten by insects so that good seed 
is ard to find ne is like that of Bigelovii. 
The flatetemmed, hid yas species are common on th 
foothills from 1000 ft. o 4000. ft. alt., thouge not restricted to it 
