Order 1. =Caryophyllaceæ.= 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_ (obdiplostemonous), _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 _A_, _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 considerably. 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_, _Cerastium_, and others, and, finally, a series of genera are formed, with certain conditions of reduction which have become constant, and by a gradual series of steps lead to the most reduced form, which has only 5 sepals and 5 (or even as far as only 1) sepal-stamens (Fig. 361 _D_, _E_, _F_).--The PETALS in the _Alsineæ_ are often deeply bifid. The sepal-stamens are most frequently the longest, and bear nectaries at the base (Fig. 363 _st_). In the most complete forms the ovary has partition-walls in the lower portion (Fig. 360); these do not, however, reach to the top, and generally soon disappear. The ovules, when numerous, are situated on the placenta in as many double rows as there are carpels. In the number of ovules a reduction from many to 1 takes place (Fig. 361). A comparison proves that the “free, centrally placed” placenta is formed by the ventral portion of the carpels. The single basal ovule in _Herniaria_ (Fig. 364), _Scleranthus_, and others, is also borne on the carpels.