( 



MAY.] HOT-HOUSE OF REPOTTING. 225 



simplex; M. pusilla, and M. cbnica, are good species, 

 and will do well with water five or six times during 

 summer. 



Melocdctus, seven species, and are those that are 

 roundish with deep and many angles, with spines in 

 clusters on the top of the angle. M. communis, is the 

 Turk's cap, named from having an ovate conate crown 

 upon the top, from which proceed the small red flowers. 



M. macrdnthus, has large spines; M. pyramiddlis, is a 

 conical growing species. These require the same 

 treatment as the last. 



Echinocdctus, about twenty species ; are those that 

 have many deep angles, and have a remarkable swell- 

 ing, with each parcel of spines ; E. gibbosus ; E. crispd- 

 tus ; E. recurvus ; are curious in appearance, with small 

 white and purple flowers. These three genera in most 

 collections are not well known specifically, but it is 

 easy to discriminate which genus they are connected 

 with. 



Cereus. This is the most magnificent genus ;vith 

 regard to the magnitude and beauty of the flowers, but 

 not so closely allied. It takes in all those of a trailing 

 or erect growing habit, having spines in clusters, soli- 

 tary, or spineless. C. peruvidnus and C. heptagbnus, 

 grow very erect, and to the height of thirty or forty feet 

 in Peru and Mexico, where they plant them close to- 

 gether as fences, and they are in a few years impene- 

 trable. C. flagelliformus is a well known creeping free 

 flowering species, has ten angles ; will keep in a good 

 Green-house, and produce in May and June a great 

 number of blooms. The petals are of a fine pink and 

 29 



