50 CACTACEOUS PLANTS. 



diameter, with creamy white lanceolate petals with an outer fringe of narrow 

 yellow sepals. The growth is, however, different, the surface of the stem 

 being covered with irregular tubercles, not distinctly ridged as in most other 

 species ; it is slender, usually half to 1 inch in diameter, and trailing. A fine 

 specimen is grown in the Cromwell House collection, trained over the wire 

 arch shown in fig. 9, p. 41, and this plant has produced flowers 14 inches 

 in diameter. Mr. W. Wright, the gardener in charge of this collection, has 

 crossed C. MacDonaldise with pollen from C. speciosissimus, which may be 

 expected to yield an interesting and beautiful progeny. The species was 

 introduced from Honduras to Kew by Mrs. General MacDonald, and first 

 flowered in the Eoyal Gardens in 1851. 



C. FLAOELLiFORMis, Ilaworth. — Under the popular names of Whip-cord 

 and Rat's-tail Cactus this plant is well known, and probably is the most 

 generally grown of all the Cereus. It is one of the oldest-known in England, 

 having been introduced in 1690 by the Earl of Portland, the same year as 

 C. triangularis made its appearance here. The plant was cultivated by 

 Miller, and was included in the Kew collection in Alton's time. In reference 

 to its habit and the number of ridges on the stem it was named by some of 

 the old writers Cactus repens decemangularis, and amongst other still older 

 titles bestowed upon it was Ficoides americanum, in reference to its native 

 country, Peru, and eontiguous districts of South America. The stems are 

 very slender, about half an inch in diameter, and they grow to the length of 

 4 or 6 feet, being of pendulous habit. At Kew there is a fine example grafted 

 upon a stem of C. rostratus 6 feet high, which has a dense cluster of branches, 

 about sixty, each 4 or 5 feet long. When flowering this has a most striking 

 effect, the bright rosy-coloured flowers, which are produced in spring and 

 early summer, being extremely attractive. Owing to its very pendulous 

 habit this species is generally seen to better advantage grafted on a stem of 

 the columnar Cereus, upon any of which it seems quite at home. When on 

 its own roots it appears to succeed best in a loamy compost, porous, but 

 heavier than is usually given to Cactese. 



Many other trailing Cereus could be named, such as C. Kapoleonis, 

 C. rostratus, C. Lemoinei, C. Karstenii, C. nycticallis, C. Cavendishi, C. ser- 

 pentinuB, and C. colubrinus, but they are mostly rare, and as regards their 

 floral attractions, those already described are preferable. Where, however; 

 the space can be afforded them they are all worth growing and for training 

 on arches like those in the Cereus house shown in fig. 9 they are extremely 

 interesting and beautiful, as by associating several together a lengthened 

 period of flowering is insured. It the wire netting be packed with moss, 

 and this is occasionally damped in hot weather, it affords all the moisture 

 the plants need. 



The true Cereuses having been noticed, the three other groups which 

 are now referred to the genus Cereus demand attention. 



EcHisocEKEUS. — In general appearance, and particularly in the 



