BRITISH FLOWERING PLANTS 



rapidly being exterminated in many places by 

 reckless gathering and uprooting. 



Plants are divided into two principal sections : 

 Phanerogamia, or those which produce true flowers 

 and seeds ; and Cryptogamia, or those which do not. 

 Flowering plants only are included in the present 

 work. The flowerless plants, including Ferns, 

 Mosses, Seaweeds, Lichens, Fungi, Diatoms, Bac- 

 teria, and various other low forms of plant life, may 

 perhaps find place in a later volume of this series. 



Flowering plants again belong to two main 

 classes— Dicotyledones and Monocotyledones. In 

 Dicotyledones the seed is divided into two halves, 

 each of which throws up a primary leaf when the 

 seed germinates. In Monocotyledones there is 

 often only one primary leaf, and the general 

 formation of the plant is very different. The 

 former class includes by far the larger number 

 of plants. To the latter belong many more or 

 less bulbous plants, such as Orchids, Flags, Lilies, 

 etc. ; many water-plants, like Reeds, Rushes, and 

 Sedges ; and the great Order of Graminece, or 

 Grasses. 



STRUCTURE OF A PLANT 



A plant consists of the following principal parts : 

 the roots, the stem, the leaves, the flowers, and the 

 fruit. 



Roots 



The roots are fixed in the ground, to support 

 the plant, but in climbing plants, like Ivy, for 

 instance, we meet with aerial roots, which cling to 

 the bark of trees or other supports. At the ex- 

 tremity of the rootlets we generally find a " root- 

 cap," which protects the growing extremity of the 

 root, and enables it to penetrate hard ground. As 

 the root grows, the root-cap also continues to grow, 

 the portion behind the tip dying off. Behind the 

 root-cap are the root-hairs. Their function is to 

 absorb water containing nourishing salts which 

 have been dissolved from the surrounding soil, 

 and to convey it to the actual roots. 



Roots are divided into primary and adventitious. 

 The primary root is formed by the prolongation of 

 the stem downwards, which, when well developed, 

 is termed a tap-root. In many plants (Orchidacece, 



