594 PHANEROGAMS. 



at the expense of the whole or part of the cellular layers of the ovular integuments \ 

 and presents extreme diversities in its structure, the ovule, together with its contents 

 which have resulted from fcrlilisation, becomes the Seed. The wall of the ovary, 

 the placentae, and the dissepiments, not only increase in dimensions, but undergo 

 the most various changes of external form and still more of internal structure. 

 Together with the seeds they constitute the I&my. The transformed wall of the 

 ovary now takes the name of Pericarp ; if an outer epidermal layer is specially 

 diiferentiated it is called the Epicarp, and the inner portion the Endocarp ; while a 

 third layer, the Mesocarp,' frequently lies between these two. A number of typical 

 kinds of fruit are distinguished according to the original form of the ovary and the 

 structure of its tissue when ripe, the nomenclature of which will be given in the 

 sequel. But sometimes the long series of deep-seated changes induced by fertilisa- 

 tion extends also to parts which do not belong to the ovary, and even to some 

 which have never belonged to the flower. But as they are part of the fruit from 

 a physiological point of view, and are usually associated with it as a whole, while 

 sharply differentiated from the rest of the plant, a structure of this kind (such as 

 the Fig, Strawberry, and Mulberry) may be termed a Fseudocarp. 



At a certain period either the fruit together with its seeds becomes detached 

 from the rest of the plant, or the seeds alone separate from the dehiscent fruit ; and 

 this is the period of maturity. In many species the whole plant dies down when the 

 fruit is ripe, and a plant of this description is termed monocarpic (bearing fruit only 

 once). Monocarpic plants may be distinguished into those which fructify in the 

 first period of vegetation {annual plants), those which do not till the second year 

 {biennial plants), and finally not till after several or a large number of periods of 

 vegetation (monocarpic perennial plants, as Agave americand). Most Angiosperms 

 are however polycarpic ; i. e. the vital power of the individual is not exhausted by the 

 ripening of the fruit ; the plant continues to grow and periodically fructifies afresh, 

 or is polycarpic and perennial. 



I. The Inflorescence''-'. It is comparatively rare for the flowers of Angiosperms to 

 arise singly at the summit of the primary shoot or in the axils of the leaves ; peculiarly 

 developed branch-systems are much ' more commonly produced at the end of the 

 primary shoot or in the axils of its foliage-leaves, which usually bear a considerable 

 number of flowers and are distinguished by their collective form from the rest of the 

 vegetative body ; in polycarpic plants these may even be thrown off after the ripening 

 of the fruit. Such a system of branching is termed an Inflorescence, The habit of the 

 inflorescence does not depend merely oi;i the number, form, and size of the flowers which 

 it bears, but also on the length and thickness of the branches of different orders, as well 

 as on the degree of development of the leaves from the axils of which the branches 

 spring. These leaves are generally much simpler in form and smaller than the foliage- 



^ [From the very extensive recent literature on the structure and development of the seed-coats 

 the following may be cited : Lohde, Ueb. d. Entwickelungsgeschichte und den Bau einiger Samen- 

 schalen, Schenk's Mittheilungen, II, i875.--Sempolowski, Beitr. z. Kennt. des Baues der Samenschale, 

 Leipsig, 1874, — Hegelmaier, Ueb. Bau und Entwickelung einiger Cuticulargebilde, Jahrb. f. wiss. 

 Bot. IX, 1874. — Chatin, Le dev, de I'ovule et de la graine, Ann. de Sci. Nat. ser. 5, t. XIX, 1874. — 

 von Hohnel, Morphol. Unters. iib. die Samenschalen der Cucurbitaceen, Sitzber. d. Wien. Akad. 

 LXXIII, 1876. — Haberlandt, Entv^^ick. und Bau der Samenschale von Phaseohis, ibid. LXXV, 1877.] 



•^ [See also Eichler, Bliithendiagramme, I, and Asa Gray, Structural Botany, 1880.] 



