398 



THE BOOK OF GARDENING. 



{P. piibescens) is less vigorous in growth, but equally free in blossom. 

 F. undulatus is a neat-growing variety, of medium height, and 

 exceptionally free in blossom. P. inodorus is less vigorous in 

 growth than P. gra7tdiflorns ; the flowers are also smaller, and 

 devoid of fragrance. As the odour of Mock Orange flowers is 

 not agreeable to everybody, this sort should be noted, as it 

 blossoms much more freely than some of its congeners, without 

 possessing overpowering fragrance, P. Satsumi^ a Japanese 

 species, grows about 6ft. high, and forms an elegant bush ; 

 the flowers are white, and borne abundantly. P. Keteleeri 

 Hore-pleno is free-flowering, and of good habit. 



P. inicrophyllus is suitable for the rock garden, as it rarely 

 exceeds 2\{\.. in height. It is slender in growth, and in summer 

 its Myrtle-like leaves are almost hidden by the wealth of tiny pure 

 white flowers. P. viicrophylhis has been the forerunner of a 

 group of dwarf-growing and exceedingly free-flowering Mock 

 Oranges, raised by that eminent French hybridist, Mons. 

 Lemoine, who commenced crossing it with a garden form of 

 P. coronarius. Some of the best kinds raised from it are : 

 Pemoinei, pure white, fine for massing in the open air, and useful 

 for forcing ; Boule d' Argent, free, with semi-double, delightfully- 

 fragrant flowers ; Gerbe de Neige, with its sw^eet-scented single 

 flowers ; and Mont Blanc, pure white. 



Platanus acerifolia (Plane Tree) is so well known that 

 description is unnecessary. It is the finest of all trees for street 

 planting, as it luxuriates in poor soils and smoky atmospheres. 

 P. a. Suttneri is of upright, compact habit, and very effective. 

 Its deeply-cut leaves are beautifully marbled and striped with 

 cream white on a pale green ground, the variegation being 

 constant in all soils. It is quite hardy and vigorous ; a fine tree 

 for the park. P. cuneata \P. digitata^ P. Jiepalensis laciniatd) 

 forms a low, much-branched tree, with glabrous wedge-shaped 

 leaves. P. orientalis is vigorous and of free growth. 



PoPULUS (Poplar) contains many hardy trees, which are of 

 quick growth and happy in nearly all soils. P. heterophylla, 

 with its heart-shaped leaves, is distinct and beautiful, and 

 grows to a height of about 50ft. ; the petioles, as well as 

 the under-surface of the leaves, are white, which gives additional 

 beauty. P. ajigulata (Caroline Poplar) is a very ornamental free- 

 growing species, especially when planted in damp soil. P. grafidi- 

 dentata grows about 50ft. high, and its yellowish leaves, touched 

 with red in spring, are very handsome. P. canescens {P. albo- 

 tremuld) is conspicuous in spring when carrying its long 

 catkins, and its pale grey leaves when disturbed by a gentle 

 breeze possess distinct beauty. It is well adapted for planting by 

 the side of lakes and on islands. P. alba macrophylla {P. Picarti) 

 is a large-leaved form of the well-known P. alba (Abele Tree). 



