5S CACTACEOUS PLANTS. 



these depressions. Several varieties and hybrids have been raised from 

 P Aokermanni by crossing it with species of Cereua, especially C. apeoiosis- 

 simus, which has yielded a race of handsome forms differing in the colour 

 and size of the flowers, but chiefly shades of crimson or red. It is also said 

 that P. Ackermanni has been successfully crossed with Cereua flagelliformis 

 in France, the plants resulting differing greatly from both parents, but I 

 have never had an opportunity of seeing these forms. A beautiful hybrid 

 between P. Ackermanni and P. crenatus has been raised and flowered in this 

 country, in whiob the inner petals were of a soft pale rosy tint and the outer 

 a deep crimson, affording a pretty contrast. One valuable character of this 

 species and its varieties is that they may be had in flower from May to 

 August or even longer than that with a good stock of plants brought forward 

 a few at a time. 



The woodcut (fig. 11) represents a flower and portion of the plant- 

 much reduced. 



P. ANGTTLiaER, Iicmaire. — An extremely distinct plant, easily recognised . 

 by the deeply angled stems 2 to 3 inches in diameter, which are indented on 

 the margin somewhat like a large saw with the teeth turned upwards, forming 

 blunt triangular lobes. The flowers, which are 3 to 5 inches in diameter, the 

 petals white, the sepals narrow, orange or yellowish, and spreading, open 

 during the day, and continue expanded for a considerable time, giving out a 

 powerful fragrance. It was found by Hartweg during bis travels in the - 

 west of Mexico growing upon trees in a forest where Oaks predominated, and 

 specimens were by him sent to the Horticultural Society. 



P. BIFOKMIS (Disocactus biformis, Lindley). — Though not equal in 

 attractiona to otber Phyllocactuses, this is an interesting plant, forming 

 in appearance a link between those species and the Epiphyllums, but it is . 

 not likely to become of much garden value, and will only be grown to make 

 a collection complete. The plant was introduced to England from Honduras 

 at the same time (1839) and by the same persons as P. crenatus, and was 

 described as a Cereus, but was subaequently constituted a genua by Lindley 

 under the name Disocactus, and by Salm Dyck under the slightly different 

 title of Disisocactus. The selection of these names was doubly unfortunate, 

 first because there is a genus termed Disoocaotus quite distinct from this, 

 and secondly because the plant does not possess sufficient characters to 

 separate it from Phyllocactus, to which it is now referred by botanists. 

 Plants in cultivation are usually rather small, but they will attain the 

 height of 3 feet, branching freely and forming a rather graceful fleshy 

 shrub. The branches are narrow, flattened and leaf-like, reddish on the- 

 margin, and bear the flowers at the points. The petals are narrow, 2 to 3 inches- 

 long, and partially combined into a kind of tube of a pale rosy pink colour 

 The flowers, however, do not last long, and are followed by bright red fruits 

 about half an inch long, which, being produced abundantly, have a rather 

 pretty effect. 



P. CEENATUS.— A magnificent species, undoubtedly one of the best in the 



