104 CACTUS CULTURE FOR AMATEURS. 



O. arbor esceiis. 



Known as the Walking-Stick or Elk-Horn Cactus, from its 

 cylindrical, woody stems being made into curious-looking walking- 

 sticks, whilst the arrangement of the 1 ranches is suggestive of elk 

 horns. Stems cylindrical, branching freely, and forming trees 

 from 8 to 30 feet high. They are covered with oblong tubercles 

 and tufts of long, needle-like spines. Flowers on the young branches 

 3 inches in diameter, bright purple, developed in June. Mexico. 

 Requires greenhouse or stove treatment. The skeletons of this 

 species, as seen scattered over the desert places where it is wild 

 have a startling appearance* They stand quite devoid of leaves, 

 spine?, or flesh, nothing remaining except a hollow cylinder, per- 

 forated with holes, where the small branches had been. These 

 skeletons are said to stand many years. 



O. arbuscula. 



Stem cylindrical, solid, woody, about 4 inches through, clothed 

 with smooth green bark ; height 7 or 8 feet. Branches numerous, 

 slender, copiously jointed, the ultimate joints about 3 inches long 

 and I inch thick, slightly tuberculated, bearing tufts of spines 

 1 inch long. Flowers produced in June 1A inches in diameter, 

 greenish-yellow, tinged with red. Mexico. A very remarkable 

 plant, the thin branches, with their hundreds of long whitish spines, 

 being striking. Unfortunately, it is not easily grown. It requires 

 stove treatment. 



O. arenaria. 



Sand loving. Stems spreading, forming a tuft 3 feet through 

 and about 1 foot high. Joints 1J to 3 inches long, terete, with 

 very prominent tub _rrcles and numerous tawny bristles, 1 to 1| inches 

 long, shorter ones hair-like and curled. Flowers 2 inches in diameter, 

 produced in May. Fruit 1 inch long, bearing a few short spines. 

 Mexico. A stout- rooted plant, which should be grown in loose, 

 sandy soil. It thrives best when planted out on a stage near the 

 glass in a stove. 



O. Auberi. 



Erect, 8 feet or more high, not unlike 0. Ficus-indica in the 

 form of its joints, but with long spines springing from the cushions, 

 whereas the latter has none. The joints are oblong-ovate, glaucous- 

 green, the cushions few and scattered ; spines white, flattened, of 

 various lengths. Flowers tawny-yellow, small for the size of the 

 plant. Cuba. Requires stove treatment. Being very brittle, 

 this plant should be supported with stakes. 



O. aurantiaca. 



Stem dwarf, cylindrical, branching freely. Joints short, J inch 

 in diameter ; spines reddish, one about 1 inch long, the otherd 

 shorter, set in cushions of white wool. Flowers bright orange, 



