224 



SCIENCE OF THE STUDY OF TREES. PART IT. 



simultaneous or continuous, the number of the flowers in proportion 

 to the leaves or surface of the plant, and whether the flowers die off 

 rapidly or slowly. The Calyx will be examined as to texture, struc- 

 ture, figure, station relatively to the ovarium and the axis of the 

 flower, surface, size, proportion to the corolla, colour, sestivation, 

 and duration. The Corolla will be viewed in its " structure, figure, 

 station with respect to the ovarium and axis of inflorescence and 

 adjacent parts, surface, sestivation, size, colour, proportion to the 

 calyx and stamens, and venation." (Littdl. Introd., p. 141.) Stamens, 

 Filaments, Anthers, Pollen, Disk, Ovaries, Ovules, Styles, and Stigmas, 

 will all be examined with a view to generic and specific definitions, as 

 well as to general description. 



h. The Fruit will be examined as to " texture, form ; whether naked or 

 covered with the remains of the floral envelopes ; whether sessile or 

 stipitate; mode of dehiscence, if any ; number of its valves and cells; 

 situation of the placentae ; nature of its axis ; number of its seeds " 

 (Ibid., p. 442.) ; magnitude in a wild state, in cultivation ; whether gene- 

 rally abundant or not abundant, conspicuous or not conspicuous ; 

 colour of the surface ; when ripe, length of time in ripening, and dura- 

 tion on the tree. 



i. The Seed will be considered scientifically in the generic and specific de- 

 scriptions, and generally with a view to populai* description. Scientifically, 

 it will be examined as to " position with respect to the axis of the fruit, 

 mode of insertion, form, surface ; the texture and nature of the testa, 

 arillus, and other appendages, if any ; position of the raphe andchalaza. 

 Albumen, its texture, if any. Embryo, its direction, position with re- 

 spect to the axis of the fruit, to the hilum of the seed, and to the 

 albumen ; the proportion it bears to the mass of the latter ; the form 

 of its cotyledons and radicle ; its mode of germination.' (Ibid., p. 442.) 

 Popularly, the seed will be considered as to magnitude, form, integu- 

 ments, facility or difficulty of separation from its envelopes, peduncles, 

 conspicuousness or inconspicuousness on the tree, duration of the vital 

 principle, &c. 



B. General Descriptions. After the distinctive characters of a species, race, 

 or variety, have been given, that species, race, or variety, will be de- 

 scribed more at length. 



a. Habit, Bulk, Figure, and Duration. The entii'e plant will first be cha- 

 racterised, as whether tree, shrub, undershrub, twiner, cUmber by 

 tendrils or by elongation, trailer, &c. ; its bulk, figure, and duration 

 will then be given, in a natural state in its native habitat, and in an 

 artificial state, more especially in British plantations or gardens. 



b. Species. In describing species, two objects will be kept in view ; the 

 first to convey a correct idea of the figure of the plant to one who has 

 never seen it, so as to enable him to recognise it ; and the second to 

 communicate such ideas respecting its nature, its roots, branches, wood, 

 seeds, &c., as may give a cultivator some notion as to how it may be 

 propagated, and to what purpose its products may be applied. 



c. Races and Varieties will be conducted on the same plan, and with a 

 view to the same result as the descriptions of species. 



d. Mules, or Hybrids. A hybrid may either be the produce of two 

 aboriginal species, such as the Pyrus spuria, in which we shall call it 

 a mule ; or it may be the produce of two races or varieties, as are 

 most of our cultivated fruits ; in which case, if it reproduces itself from 

 seed it is a race, but if it can only be propagated by division it is a 

 variety. 



e. Variations. Variations differ from varieties in not being capable of 

 being continued by propagation. The susceptibility of individuals to 

 vary in their appearance with change of soil, light, or shade, or other 

 circumstances ,• such as the flowers of the hydrangea becoming blue in 



