364 DICOTYLEDONES. 



in certain genera of the Carijophyllacex, in the Chenopodiacese, 

 Amarantacese, and others. When the number of stamens is in- 

 creased to more than 5 in the whorl, it is always possible to show 

 that some of the stamens have been divided. The number of the 

 carpels and ovules also becomes reduced ; in the highest there is a 

 central placenta, not free in its early stages, with a large number 

 of ovules ; in those which are most reduced there is only a single 

 ovule, which is placed centrally at the base of the ovary (Fig. 364). 

 Somewhat corresponding changes are found in the fruit, which is a 

 many-seeded capsule in those which have many ovules, but a one- 

 seeded nut where there is one ovule. In the most reduced forms 

 the flowers are generally unisexual. Similar features are also pre- 

 sent in the vegetative parts. Almost all the species are herba- 

 ceous, the leaves are simple and most frequently without stipules. 

 The structure of the stem, especially in Chenopodiaceas, Amarantacese, Nyctagi- 

 niaceae and others, often differs from that of the ordinary Dicotyledon. In the 

 woody portion of the stem and root several rings are sometimes formed which 

 resemble annual rings hut which are formed by new cambium-rings arising out- 

 side the old ones which then cease to divide. 



Order 1. Caryophyllacese. Herbaceous plants, with round, 

 nodose stem ; leaves opposite, slightly amplexicaul, simple, with 

 sessile, undivided, entire lamina; stipules nearly always absent ; the 

 inflorescences are dichasia passing over into unipared scorpioid 

 cymes. The flowers are regular, $ or unisexual, hypogynous or 

 perigynous, 5- (or 4-) merous with 2-3-4-5 carpels ; calyx persistent ; 

 corolla polypetalous. The ovary is unilocular (or originally, and 

 sometimes also in the later stages, plurilocular below, e.g. Viscaria}, 

 with free styles and 1-several curved ovules on a central, free 

 placenta. The fruit is a nut or a capsule opening apically with 

 long or short valves (teeth, Fig. 362), equal to or double the carpels. 

 For the seeds refer to the family. In Dianthus the embryo is straight. 



The flowers which are most complete have Sn, Pn, An + n (obdiplostemo- 

 nous), Gn where n 5 (Figs. 360, 361 A) or 4 (Fig. 361 B) ; the carpels may be 

 placed opposite to the sepals (Fig. 360) or opposite to the petals (Fig. 361-4, B). 

 Without any change taking place in the position of the other whorls, the 

 carpels are next found reduced to 2-3-4 (see the genera) ; their number may 

 easily be recognised by that of the styles. This is the construction in the 

 majority of the genera in the two first groups. Stellaria media differs consider- 

 ably. It may have (a) the flower as described above, with G3 ; (b), the corolla 

 only absent, or (c) only the petal-stamens (A5 + 0, Fig. 361 C), or (d) all these as 

 well as some of the sepal-stamens. The same applies to Sagina, Alsine, Ccras- 

 tiurn, and others, and, finally, a series of genera are formed, with certain condi- 



