768 THE SUBDIVISIONS OF THE VEGETABLE KINGDOM. 



pollen, which ripens effectually. The Campanales are distributed over all quarters 

 of the globe. The CampanulaceiB are mostly natives of the North Temperate 

 Zone, the Lobeliacese of the South Temperate Zone and the Tropics. Some 

 Campanulaceae are also found amongst the flora of the Arctic regions, and of high 

 mountains. The Stylidiaceae and GoodeniaceEB are confined to Australia. No 

 fossil remains have been discovered. The number of identified species now living 

 is about 1300. 



Alliance XLIX. — Ericales. 



Families: BiapensiacecB, Pyrolacece, Monotropacece, Lennoacece, ArhutaceoB, 

 RhodoracecB, Ericacece, Epacridacece, Empetracece, Ebenacece, Sapotacece. 



Perennial herbs, shrubs, and trees. Flowers actinomorphic and zj-gomorphic, 

 hermaphrodite, pseudo-hermaphrodite, monoecious, and dioecious. The floral-leaves 

 arranged in two 3-5 partite whorls. The lower whorl constitutes a calyx, the 

 upper a corolla. The petals are free in Pyrolacese and Monotropacese; in the other 

 families they are coherent, at any rate at the base. The gynseceum is composed of 

 3-10 carpels; the ovary is superior, and 3-10 celled. The ovules arise from an 

 axile placenta. The andrcEcium is composed of one or more whorls of 4-5 stamens 

 each. In many cases some of the stamens are metamorphosed into gland-like 

 structures. The fruit is a capsule, berry or drupe. The embryo is erect, and 

 imbedded in the fleshy endosperm. 



The Diapensiaceae and Pyrolacese (see figs. 277''*' p. 273), are perennial herba- 

 ceous, or sutfruticose plants, which grow in black humus, and have stiff, evergreen 

 foliage-leaves; the Monotropaceaj and Lennoaceaj are parasites or saprophytes 

 (see vol. i. p. 252), and are destitute of chlorophyll. The Arbutacere, Rhodoracese, 

 Ericaceae, Epacridacese, and Empetraceas are, for the most part, dwarf shrubs; only a 

 few are trees. Erica arborea, one of the MediteiTanean Flora, when able to grow 

 without hindrance, attains the height of 8 metres. The branches of Ericacefe, Epa- 

 cridacese, Empetraceae, and of Loiseleuna or Azalea procuvibens, one of the Rhodoraceaj, 

 are thickly covered with stiff, rolled leaves (see vol. i. p. 303^). The species of the 

 genus Rhododendron have flat foliage-leaves (see Plate X.), as have also the 

 Arbutaceae (see tig. 433'). The leaves of Arctostaphylos alpina, Azalea Pontica, 

 and A. mollis are green in the summer only, whilst most of the Arbutaceje and 

 Rhodoracese have flat, evergreen foliage. The Ebenaceae and Sapotacese exliibit, 

 in a large proportion of their species, arboreal growth and leathery foliage-leaves. 

 All the Ericales are distinguished for their solid timber. Some of the Rhodoracese 

 have zygomorphic flowers; the rest of the Ericales have actinomorphic flowers. In 

 Loiseleuria, and in the Empetracese and Epacridaceae, the androecium is composed 

 of one whorl; in the others it consists of two or more whorls. The anthers of 

 Arbutaceae and of many Ericaceae possess two peculiar horn-like appendages (see 

 figs. 433* and 433*. and figs. 216 ^-i""' p. dl). In Epacridaceae the anthers are 

 unilocular, and dehisce longitudinally; in Ericaceae, Arbutaceae, Rhodoracere, and 

 Pvrolaceae they usually open by terminal chinks or pores (see p. 91, tigs. 216 *• *> ^°' ^'' ^^). 



