8 CLASSIFICATION OF PLANTS. 



&c., so, among seedling plants, from the same seed-pod, no two plants will 

 be found exactly alike ; and some will occasionally differ considerably from 

 all the rest. Nevertheless, it is an undoubted fact, that all seedling plants 

 not only possess the character of the species from which they have sprung, 

 but even, in by far the greater number of cases, some of the peculiarities of 

 the individual. The seeds of any kind of cultivated apple, for example, 

 will produce plants, the fruit of all of which will more or less resemble that 

 of the parent ; though perhaps some one or two among a hundred may be 

 considerably different. Hence, by selecting from beds of seedling plants those 

 which are in any way remarkably differert from the rest, new varieties are 

 procured ; and, till within the last half century, (when artificial cross- 

 breeding began to be practised by gardeners,) this was the only way in which 

 an improved variety of any species of plant was procured. If the seeds of 

 varieties did not produce plants closely resembling their parents, how could 

 all the improved varieties of culinary, agricultural, and floricultural plants, 

 be perpetuated ? That the same law which governs herbaceous plants holds 

 good in trees and shrubs cannot be doubted ; and if the seeds of a variegated 

 tulip are more likely to produce plants which shall have variegated flowers 

 than those of a tulip of only one colour, so we should say the berries of a 

 variegated holly are more likely to produce plants with variegated leaves 

 than those of a green-leaved holly. If this law did not hold good in ligneous 

 as well as in herbaceous plants, how are we to account for the different 

 varieties of Hibiscus syriacus coming true from seed ? 



17. Plants, like animals, are subject to various diseases, as well as to be 

 preyed on by insects, most of which live on plants till they have completed 

 their larva state. Plants are also injured by being crowded by other plants, 

 either of the same or of different species. When these spring up naturally 

 around the cultivated plants, they are called weeds, and the cultivated 

 plant is cleared from them by weeding ; as it is in the case of being crowded 

 by its own species, or by other cultivated plants, by thinning. Plants are 

 also injured by epiphytes, which grow on the outer bark, such as mosses and 

 lichens ; and by parasites, which root into their living stems and branches, 

 such as the mistletoe, &c. 



18. The life of plants, like that of animals, is limited, but varies in regard 

 to duration. Some plants vegetate, flower, ripen seed, and die, in the course 

 of a few months, and these are called annuals ; while others, such as the oak 

 and some other trees, are known to live upwards of a thousand years. 

 In both plants and animals decay commences the moment life is extinct ; 

 and in both they are ultimately resolved, first, into a pulpy or other homo- 

 geneous mass, fit for manures, and ultimately into certain gases, salts, and 

 earths. After death, the decay both of animals and plants may be retarded 

 by the same means; viz., drying, exclusion from the air, or saturating with 

 saline or antiseptic substances. 



SECT. II. Classification of Plants ', with a View to Horticulture. 



19. The number of plants is so immense, and the diversity of their ap- 

 pearance so great, that without some kind of classification or arrangement 

 it would scarcely be possible either to receive or retain any distinct notions 

 respecting them. In communicating some positive knowledge of plants, 

 therefore, the first step is to show the mode of simplifying this knowledge 

 by throwing plants into classes, and other divisions or groups. 



