Page:Illustrations of Indian Botany, Vol. 2.djvu/92

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ILLUSTRATIONS OF INDIAN BOTANY. Sksuviaceaf.. — Calyx. 5 parted, petaloid within. Corolla none. Ovary one (by abortion ?) or several celled, placenta in the axis of the cells, or when one-celled, cohering to the side : ovules several, superposed, attached by longish podosperms. Capsule usually becoming one-cell- ed by the obliteration of the partitions, or, spuriously, transversely 2-celled, circumscissile (dehiscing transversely) little above the base. — Succulent herbaceous plants. Triartlhema, >$e- svvium.

Paronicheaceae. — Sepals 5, more or less cohering at the base, persistent : petals 5, shorter than the calyx, inconspicuous, or somewhat imperfect, marcescent. stamens 5, or three, by abortion, shorter than the calyx : capsule I -celled. 3-valved : placenta central in the base of the cell with numerous seed attached by distinct podosperms to the base. Po/ycarpea, Hapalosea, Drymaria.

Mollugineae. — Sepals persistent : corolla wanting or imperfect, the petals resembling sterile stamens : stamens 5-lU sometimes 3 by abortion : ovary free 3-5-celled, placenta in the axis of the cells, extending their whole length ; ovules numerous superposed : capsule 3-5-celled dehiscence loculicidal. Mollugo, Glinus, ? Orygia.

To this last genus our Glinus trianthemoides belongs. It is referred to this section by Endlicher and Meisner, but. having a perfect corolla may possibly yet find a more suitable station, though for the present I can propose no better place.

In this distribution I have excluded the name Ficoideae, which has especial reference to Mesernbryanthemum — the Fig marigold— a Cape genus of great extent and differing, in appear- ance, most widely from all the rest of the tribe, not only in its flowers, which are curious, much resembling a radiate composita, but in its fruit, which is very remarkable, but with the struc- ture of which, Botanists, though the plants are now cultivated in every green house in Europe, seem imperfectly acquainted. Professor Endlicher (Genera plantarumjis the only writer, so far as I am aware, who has described its appearance, with sufficient accuracy to lead to the suspicion that it presents any marked peculiarity. DeCandolle describes the ovary as from 4 to 20- celled adnate within the substance of the calyx. ( Ovarium calyci adnatum intus pluriloculare ( 4-20 ) saepius 5—loculare J the capsule as many celled adnate to the calyx and dehiscing in a star-like manner at the summit. No one would suspect from this any peculiarity. Endlicher however takes a different view. He describes the ovary as composed of from 4 to 20-carpels, horizontally verticelled round a thick central axis, with the margins of the carpels, forming the ventral suture free above, or valvately connate, or introflexed forming a moie or less perfect spurious partition. Placentas linear, adnate to the middle nerve of the carpel, occupying the bottom of the cell."*

According to this description the usual position of the placenta and consequently of the whole carpel is reversed. The normal structure of a carpel is, for the ventral secture to be placed in the axis and there bear the placenta. Dehiscence, when loculicidal then takes place along the dorsum, or middle nerve, on the side most remote from the axis. Here, according to the above description, we find matters wholely reversed, the dehiscence is loculicidal, but in the place of the dorsum splitting to give passage to the seed, the ventral suture, which in other plants is central and bears the seed, is said to be free and to open to give them passage ; while the placentas, in place of being produced by the union of the margins of the carpellary leaves, is said to be generated by the midribs or costee. Can such an inversion really happen ? I certainly think not, and, therefore, suspect the learned author has fallen into error in supposing the ventral suture of the carpels free and dehiscent, in place of, as they appear to me, attached to a broad gynobase, which, by raising the dorsal face of the carpel from the horizontal to the vertical aspect, produces an appearance of inversion that does not. exist. According to this view, which however I offer with considerable diffidence as my acquaintance with the fruit of this genus is altogel her derived from the examination of dried specimens of three or four species, the flowers are not epigynous,

horizontaliter veticillatis 4-20-loculare, carpidiorum inarginibus suturam ventralem Buperam cons-titueiitibus valvatim eonnatis v. in septum plus minus distincte introflexis Placenta; linearis car^idioruin nervo medis adnate lundum loeuli occupantes." Eudl. Gen. PI. p. 945-6.
 * Ovarium cum calycis tubo connatum, e carpidiis 4-20 conflatum, carpidiis circa axim centralem crassam sub-