a ( Opuntia arborescens ) grows sometimes to be almost a tr ae 
_ covered with a mass of the most awful looking, and feeling thom 
984 Botanical Notes from Tucson, [ December, 
seen a long way, and doubtless serves to attract birds who can 
thus disseminate the seeds. 
There is no more striking and conspicuous form of vegetation 
than this Cereus giganteus. It often grows to the height of thirty 
feet, straight as an arrow and of nearly the same size from bot- 
tom to top. The internal framework is made up of a number of 
hard woody cylinders, the spaces between being filled up by 
pithy matter; sometimes it is branched, but in a stiff and un- 
graceful manner, the branches jutting out almost at right angles 
and then turning and ascending parallel to the parent stem. Sit- 
ting on the rocks near some of these plants, when the wind was 
blowing strongly, the sound of it passing between the spines 
resembled strikingly the soughing of the wind through the 
branches of a pine tree; and shutting the eyes it required but 
little imagination to be transported to a northern pine forest, lis- 
tening to the wind blowing through the branches. It is strange 
that the action of the wind in two such different localities as the 
hot deserts of the South and the cool mountains of the North; 
and playing upon two such different types of vegetation as a cac- 
tus and a pine tree, should produce sounds so similar to each 
other. 
Another species of the family is one commonly called the 
“nigger-head” or “barrel” cactus, a Mammalaria. This often 
grows four feet high, sometimes only half as much, and almost 
globular in shape. It has many ribs converging to the top, and 
each bears innumerable clusters of spines. The lower ones are 
long, straight and horizontal; some of the central ones stand 
upright and the largest in each cluster is curved over so as t© 
form a sharp hook. These are very tough, and while the crooked 
ones serve the Indians for fish hooks, the straight ones are 
used as needles. The flowers of this species are generally se 
A much smaller species of this form, also a Mammalaria, 1s eee 
common among the rocks on the mountains near the city. The 
spines are black and very small, but sharp. Still another species 
ee, and is 
__ These seem to be covered witha sort of sheath, easily removed, an 
ee _€asily sticking into one’s fingers. The thorns are sharp enone 
: long enough to go through pantaloons and boot top, and stick ¥ 
Ciously in be 
into the skin. The Mexicans call this the “ochoya” cae: : 
