DISOOCACIUS. 39 



The woodout, fig. 7, has been prepared from a photograph of one of 

 Mr. Peacock's fine plants, which unfortunately have now been lost. These 

 were about 2 feet high and as much in diameter, and continued in vigorous 

 health for several years, but ultimately were damaged by a " drip " from 

 the roof of the house, and rapidly decayed, despite the care exercised to 

 prevent it, 



DISCOCACTUS, Pfeiffer. 



The two or three species which have been assigned the generic nan e 

 of Discocactus are amongst the least interesting members of the whole 

 family, and certainly their horticultural value is small. They are 

 dwarf and semi-globose in form, very suggestive of an Bchinocactus in 

 appearance, and some writers have thought that the two genera were 

 not sufficiently distinct to be separated. It must not, however, be con- 

 founded with the Disocactus or Disisooactus biformis of Lindley, which 

 is a totally different plant, now referred to Phyllocactus. The principal 

 characters adopted by Hooker and Bentham are the following : — 

 Calyx and tube extending beyond the ovary, slender ; base naked, 

 smooth ; lobes indefinite, exterior reflexed, interior larger. Petals in two 

 series, spreading, interior smaller. Stamens indefinite ; filaments adnate 

 to the tube of the calyx, interior longer ; anthers small. Stem depressed, 

 ribbed ; ribs few. Flower usually solitary from the apex of the plant, 

 and fragrant. 



The species are natives of Brazil and the "West Indies, inhabiting 

 ■dry sandy regions, and are found rather difficult of cultivation, and at 

 the present time I do not know one collection which contains living 

 plants. They require a warm sunny position and great care in supply- 

 ing water, as the slightest excess results in the death of the plants. 



D. lusiGNls, Pfeiffer. — This is the best known, and is chiefly noteworthy 

 for the fact that its flowers possess an extremely agreeable fragrance, which 

 has been compared to that of Orange blossom. The stem is semi-globose, 

 with nine or ten obtuse ridges, and a crown of white wool-like substance, 

 from which are produced the long and slender flowers, having the sepals 

 pink, and the petals white or blush-tinted. D. alteolens has the stem of a 

 much darker green colour, and flowers' with a less pleasing odour. 



CEREUS, Sawortli. 

 (The Torch Cactus.) 

 Leaving the globose or tubercled Cactese represented by those pre- 

 -viously described, we find in Cereua a greatly different mode of growth, 

 ■the stem being greatly elongated, usually of small diameter in propor- 

 tion to its height, frequently much branched, but bearing parallel ridgea 



