CACTI FOR AMATEURS 367 



one part of sandstone or broken bricks, crushed to the size of a walnut, 

 and from that size downwards to dust. As small pots as possible must 

 be used, filling them nearly half-full of crocks. Any plants that have 

 well filled the pots with roots should be assisted with occasional appli- 

 cations of weak liquid manure. 



When it can be managed, better results can be obtained by forming 

 a rockery in the house, and planting everything out, and too much cannot 

 be said in praise of this method. In this way they grow much quicker, 

 are more at home, and infinitely more pleasing to the eye than when 

 placed in rows of pots. Many are particularly well adapted for planting 

 in crevices between stones, and grow much better in this way than 

 in pots. 



Propagation may be effected by means of seeds, cuttings, or grafting. 

 Seeds should be sown as soon as received, and when the tiny plants are 

 large enough to handle, prick them off in a bed of sandy soil in a sunny 

 position near the glass. Cuttings should be allowed to dry for several 

 days before insertion in sandy soil. Very little water must be given 

 until they are rooted. Cuttings from an inch long to several feet may 

 be used. Grafting is resorted to in a few instances only, principally 

 with Epiphyllums (see p. 368). 



Insect pests are best kept under by means of fumigating, and by the 

 use of insecticides. A useful insecticide is made by mixing a quarter of 

 a pint of paraffin in four gallons of strong soft-soap water. Mealy bug 

 and thrips are the two worst insects. 



Cacti that have been injured during importation, or from other 

 causes, and are beginning to rot should have all decayed matter cut away, 

 and be painted with carbolic acid or Condy's fluid several times, and left 

 in a sunny position until thoroughly dry. Afterwards an occasional 

 dusting with charcoal will keep them right. 



Turning to the 



Selection of Suitable Plants, the most worthy are found in the 

 following genera : Cereus, Echinocactus, Epiphyllum, Mamillaria, 

 Melocactus, Opuntia, Pereskia, Phyllocactus, and Rhipsalis. With few 

 exceptions they are confined to South America and the West Indies, the 

 headquarters being California, Mexico, and Texas. Of 



Cereus alone in which the three genera, Echinocereus, Echinopsis, 

 and Pilocereus, have been merged nearly two hundred species are in 

 cultivation. The different species vary greatly in habit, some being but 

 a few inches high, and forming dense tufts of spiny growths, others, 

 as in the case of the Giant Cactus of California, making tall, massive, 

 sometimes single, sometimes branched, columnar stems several tons in 

 weight. Another section well represented by the Old Man Cactus 

 (Cereus senilis) makes tall stems, terminated with a large mass of long 

 white hairs ; while yet another is well marked by having long, thin, 

 climbing, or scandent stems. In some instances the stems are nearly 

 round, and slightly angled ; in others they are very deeply ribbed or 

 angled, and in most cases they are very spiny. The flowers are borne 

 from the sides of the stems in summer, and in many cases are very 



