152 HOT-HOUSE — OF REPOTTING, ETC. [May. 
species, and will do well with water once a week during sum- 
mer. (Soil No. 15.) 
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. tnacrdnthus has large 
spines; M. pyramiddlis is a conical growing species. These 
require the same treatment as the last. (Soil No. 15.) 
Echinocdctus, a great number of species ; are those that 
have many deep angles, and have a remarkable swelling with 
each parcel of spines ; E. gibbdsus, E. crisjxltus, E. recurvus, 
E. roddnthia, and E. scopct, 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 with which genus they are connected. (Soil 
No. 15.) 
Cereus. — This is the most magnificent genus with regard 
to the magnitude and beauty of the flowers, but not so 
closely allied in character. It takes in all those of a trail- 
ing or erect growing habit, having spines in clusters, solitary, 
or spineless. C. semh's is the celebrated monkey cactus. C. 
peruvtdnus and C. heptagbtvas grow very erect, and to the 
height of thirty or forty feet in Peru and Mexico, where 
they plant them close together as fences, and they are in a 
few years impenetrable. C. fiagelliformis is a well-known 
creeping 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 red colour ; the 
tube of the flower is long, and will stand a few days in per- 
fection, when others come out successively for the space of 
two months, and during their continuance make a brilliant 
appearance. G. grand ijivr us is the celebrated " Night- 
blooming Cereus." The flowers are very large, beautiful 
and sweet-scented. They begin to open about sundown, and 
are fully expanded about eleven o'clock. The corolla, or 
rather calyx, is from seven to ten inches in diameter, the 
outside of which is a brown, and the inside a fine straw yel- 
low colour ; the petals are of the purest white, with the stamens 
surrounding the stile in the centre of the flower, which add 
to its lustre, and make it appear like a bright star. Its scent 
is agreeable, and perfumes the air to a considerable distance ; 
