114 GARDENING INDOORS AND UNDER GLASS 
Opuntia senilis, the dwarf prickly pear, is very 
similar to the above, but indoors makes a larger 
plant usually, although much smaller in its natural 
habitat. 
Anhalonium fissuratum, the Living Rock, is an 
other frequently encountered and very interesting 
sort. 
The Mammiullarias are compact, neat little 
plants quite unique and attractive in spite of 
their spiral rows of vicious spines. They grow only 
a few inches high and have inconspicuous pale 
flowers of yellow, red or purple, followed by the 
bright red little fruits which are one of the most 
interesting characteristics. MV. bicolor is one of the 
best and most frequently encountered sorts. M. 
plumosa has fuzzy spines, like the Old Man cactus. 
It can be kept clean by growing under a large glass. 
There are several succulent plants quite closely 
resembling cacti, which need about the same treat- 
ment. 
The century plant (Agave Americana) is uni- 
versally known. There are two sorts frequently 
seen, that with the green leaves and a variety with 
broad yellow bands which is much handsomer. 
They make excellent formal tub plants, standing 
almost any hardships and lasting for years. They 
are easily propagated from suckers and grow quite 
rapidly. They are, however, in the larger sizes very 
difficult to handle, armed with spines at leaf tips 
