Page:Illustrations of Indian Botany, Vol. 2.djvu/26

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ILLUSTRATIONS OF INDIAN BOTANY.


GEOGRAPHICAL DISTRIBUTION. Found widely distributed over Asia but every where cultivated. Arabia is however supposed to be its native country.}}

MEDICAL PROPERTIES. For these see Myrtaceae the order under which I at first included this genus.

EXPLANATION OF PLATE 97.

1. Punica granatum, flowering branch—natural size.
2. Flower and ovary cut vertically.
3. Ovary cut transversely, section near the apex of the ovary; apparently the section seen and described by Don.
4. Stamens.
5. A young fruit cut transversely, showing the parietal attachment of the upper row of carpels.
6. A seed covered with pulp.
7. The same cut transversely.
8. The same more highly magnified, showing the spirally convolute cotyledons.
9. A longitudinal section of the seed showing the embryo in situ.
10. Cotyledons unrolled—all more or less magnified.

For further dissections of the ovary of this plant see plate 97.


LXV.-MYRTACEÆ.

This is a large and very natural order, especially as now limited by the exclusion of the albuminous seeded genera, which Lindley, in the last edition of his natural system, has kept distinct under the names of Barringtonieae Lind., Lecythedeœ Richard, and Philadelpheae Don. To this arrangement Meisner objects, and recombines the whole under his order Myrtineae, forming tribes of those groups which others have thought ought to be considered distinct orders. With the limited means I possess for examining this question, it would ill become me to attempt to set myself up as umpire between such accomplished Botanists, but, I will so far depart from the arrangement already adopted in our Prodromous, as to follow Lindley in viewing the section Barringtoneae as at least a suborder, on account of its very remarkable seed and general habit, which appears to distinguish it sufficiently from the rest of the order.

I have at different times before expressed doubts of the propriety of attaching so much importance to the absence or presence of albumen, until we have attained such an acquaintance with its functions in the vegetable economy as might enable us to assign a uniform value to characters taken from it, and would not therefore now insist on its being pressed into service unless supported by other characters. On these grounds, I should hesitate to separate Philadelpheae the habit of which sufficiently accords with true Myrtaceae, simply because of their albuminous seed and leaves without dots, but as they besides differ in the aestivation of the corolla, in having distinct styles, and serrated leaves, all of which are absent in true Myrtaceae, there certainly seems much reason on the side of those who propose their separation, at the same time, it is quite undeniable, that the present fashion in Botany seems to run too strongly in that direction and that we are but too apt on barely sufficient grounds to divide families that might better be kept together, which, as in some other instances, may perhaps be the case here.

The order for the most part consists of trees or shrubs with opposite leaves, perforated with pellucid dots and abounding in fragrant resinous oil. The inflorescence is very variable, often axillary, and sessile occasionally, as in Syzygium, forming large corymbose cymes. The flowers are usually either white or red, seldom yellow and never blue.

"Calyx 4-5-6-8-cleft, the limb sometimes cohering in two portions, sometimes in one and then falling off like a cap or lid. Petals perigynous, as many as the segments of the calyx and alternating with them, sometimes slightly united at the very base; rarely wanting: aestivation imbricated. Stamens inserted with the petals, rarely as few, sometimes twice as many, usually indefinite : filaments either all distinct or monadelphous or variously polyadelphous, in aestivation curved inwards : anthers ovate, bilocular, small, bursting longitudinally. Ovarium cohering with the tube of the calyx, formed of two or more carpels, the dissepiments rarely imperfect, and hence 1 -to 15-celled : style and stigma simple. Placentæ in the axis or rarely parietal. Fruit dry or fleshy, dehiscent, or indehiscent, 2-6-or many celled, or by the obliteration of the dissepiments 1-celled. Seeds rarely solitary or few, usually indefinite. Albumen none. Embryo straight or curved : radicle next the hilum : cotyledons distinct, or sometimes