154 HOUSE PLANTS 



Of the same general type is the sea-urchin 

 cactus (Echinopsis). If it were not for the 

 ridges these plants would look like gourds 

 standing on their small ends. They some- 

 times reach a diameter of twelve inches, but 

 as grown in the window garden, rarely exceed 

 half that size. The stem has anywhere 

 from a dozen to eighteen sharp ridges. The 

 flowers are about six inches long, trumpet- 

 shaped, and either red, pink, or white. The 

 two most commonly grown species are E. 

 multiplex, with rose-red flowers, but blooming 

 seldom, and E. Eyriesii, which has white 

 flowers produced freely. 



One of the most curious is the living rock 

 cactus (jinhalonium Engelmanni, known 

 in the trade as A. £ssuratum)y sometimes 

 also called "dry whiskey," because a very 

 strong, intoxicating drink is made by crush- 

 ing the plant and adding a little water. 



Among the very smallest are the mammil- 

 larias, seldom growing over six inches high. 

 They get their name because they are cov- 

 ered with tubercles, instead of ridges. These 

 are usually set in rov>^s which twist spirally 

 around the plants. On the end of each 

 tubercle is a cluster of small spines. The 



