770 THE SUBDIVISIONS OF THE VEGETABLE KINGDOM. 



Alliance L. — Vacciniales. 

 Families: Vacciniaceoe, Oxycoccacece. 



Woody plants, presenting all gradations in form, from that of delicate dwarf 

 shrubs lying upon the ground to that of stately trees. The foliage-leaves arranged 

 spirally, exstipulate. Flowers in racemes and fascicles, or solitary; actinomorphic, 

 hermaphrodite. Floral-leaves differentiated into calyx and corolla. The calyx is 

 composed of a whorl of 4-6 sepals. The calyx-tube clothes the inferior ovary; the 

 calyx-limb is in the form of short, green teeth, crowning the top of the ovary. 

 The corolla consists of a whorl of 4-6 petals; the petals are united or free. The 

 gynasceum is composed of 4-6 connate carpels. The ovary is inferior and 4-6- 

 locular. The placentas are axile. A honey-secreting tissue is situated on the 

 top of the ovary. The andrcEcium consists of two whorls with 4-6 stamens in 

 each. The stamens surround the nectary, and are free from one another and from 

 the corolla. The members of the outer whorl are opposite the petals. Tlie fruit 

 is a berry or a drupe. The seed contains a fleshy endosperm. 



The Vacciniales have no laticiferous tubes or latex. In Vacciniacese the petals 

 are united, and the anthers are furnished with horn-shaped appendages, in Oxy- 

 coccacese the petals are free, and the anthers have no horns. The Vacciniales are 

 distributed in all quarters of the globe, and in all latitudes. The species which 

 belong to the Temperate Zones grow in peat-bogs and in the humus of woods and 

 heaths, the species native to the mountains of tropical regions are, in some cases, 

 epiphytic on the bark of old trees. Many are of social habit, and cover extensive 

 tracts of ground. This is the case, for instance, with the various species of the 

 genus Vaccinium: the Cow-berry {VacciniuTn Vitis-Idcea), the Bilberry (Vac- 

 cinium Myrtillus), and Vaccinium uliginosum. These species are also found 

 within the area of the Arctic Flora. VacciniuTn uliginosum, ranges furthest to the 

 North, and in Greenland forms with the dwarf Birch (Betula nana) and dwarf 

 Willows, a low undergrowth which reaches to 73° N. Lat. They clothe the moun- 

 tain sides in the Central Alps as far as 2400 metres above the sea-level. Fossil 

 remains have been found in the deposits of the Mesozoic, Tertiary, and Diluvial 

 Periods. The number of extant species hitherto recognized amounts to about 350. 



Alliance LI. — Primulales. 

 Families: Primulacew, Plumbaginacece, Myrsinacece. 



Annual and perennial herbs, shrubs, and small trees with alternate, opposite, and 

 verticillate foliage-leaves. Fowers solitary, or in spikes and racemes; actiuomorphic, 

 hermaphrodite or pseudo-hermaphrodite. The floral-leaves are arranged in two 

 whorls of 4-8 segments each. The lower whorl constitutes a calyx, the upper a 

 corolla. The petals are coherent. The pistil is superior, 5-carpellary, unilocular. 

 The ovules are supported in the middle of the ovary on a column of varying length 



