534 
PHANEROGAMS. 
AN Gl OS PERMSI. 
Monocotyledons and Dicotyledons are distinguished from Gymnosperms by 
the following characters: — their ovules are formed within a receptacle, the Ovary; 
the endosperm originates in the embryo-sac only after fertilisation, — characteristics, 
the importance of which has already been shown in the general introduction to 
Phanerogams. Concurrently with these distinctions there are however a number 
of other peculiarities in these plants taken as a whole which distinguish them from 
Fig. ^^q.—Akcbia qnuiata; A part of an inflorescence, 9 female, ^ male flowers ; B a male flower cut through length- 
wise, cits sterile carpels; C horizontal section of a female flower (magnified); D horizontal section of a male flower; 
E gyn.ieceum of the female flower with the sterile stamens a; an ovary cut through horizontally ; G an ovule ; H horizontal 
section of an anther; a (in B and C) the outer, a' the inner stamens, c (in E) the carpels ; / (in j5 and C) the perianth. 
all other vascular plants ; and this is especially the case with the structure of the 
flowers and the fruit, the normal morphological relations undergoing such peculiar 
combinations and changes that a more detailed description of them must precede 
the special description of the two classes which they include. 
The Flower as a whole'^. The flower of Angiosperms is rarely terminal, i.e. the 
primary stem, which is a prolongation of the axis of the embryo, rarely terminates 
^ From o.'yyeToi', a receptacle, capsule, ovary, and ffirip/^a, seed. 
^ The most important and comprehensive vv^ork on the flowers of Angiosperms is Payer's Traite 
d'Organogenie de la Fleur (Paris 1857), with 154 i^lates. Also Van Tieghem, Rech, sur la structure 
du pistil (Mem. des savants etrangers, XXI. 1871), and his notes in the French edition. [Eilcher, 
Bliithendiagramme, and Gray, Structural Botany.] 
