# Illustrations of Indian Botany, Vol. 1/Zygophylleae

XLVII.-ZYGOPHYLLEAE.
This is a small order of tropical plants of which the Indian peninsula only presents two species, but referable to different genera, both mere weeds. In America however, some of the species, among which is the Guaiacum or Lignum vitae, attain a great size and afford very fine close-grained timber. The absence or presence of albumen in the seed seems in this order to be of small account, since in our two genera one (Fagonia) has it, and the other (Tribulus) is without.
" Flowers bisexual, regular. Calyx 4-5 divided. Petals unguiculate, alternate with the sepals : aestivation usually convolute. Stamens twice as many as the petals, hypogynous : filaments distinct, dilated at the base, and usually arising each from the back of a scale: anthers 2-celled, opening longitudinally. Ovarium simple, more or less 4-5 furrowed, 4 5 celled : ovules in pairs or more, pendulous, or rarely erect : style simple, often 4-5 furrowed : stigma simple, or 4-5 lobed. Fruit capsular, or rarely fleshy, with 4-5 angles or wings, 4 5 valved and loculicidal, or indehiscent : endocarp and sarcocarp combined. Seeds usually fewer than the ovules. Albumen between fleshy and horny, rarely 0. Embryo green : radicle superior : cotyledons foliaceous.—Leaves opposite, stipuled, not dotted, rarely simple."
Affinities. Most Botanists agree in considering them nearly allied to Rutaceae, from which however they are readily distinguished by the want of pellucid clots in the leaves, which are always present in the other. They are also allied to Oxalideae between which orders DeCandolle places them, separating them from the latter by their single not several styles, by their stipulate opposite leaves, and by their seed not having an arillus. This last mark is of less
​value as it doss not seem constant in Oxalideae. From the former, in addition to the absence of pellucid dots, they differ in wanting the elastic structure of the carpals so remarkable in the true Rutaceae.
Geographical Distribution. Species of this family are found in every quarter of the globe Europe, Africa, Asia, America, and New Holland. Fagonia and Tribulus are both found in the south of Europe as well as in India. The former abounds in the Ceded Districts and also in Mysore, but I have never seen it in the Carnatic, the latter, Tribulus, is one of the most common weeds all over India, and a very troublesome one, owing to the thorns with which its carpels are armed.
Properties and Uses. The roots and leaves of Tribulus are said by native practitioners to be diuretic, the latter are used by the natives as a pot herb and are esteemed very cooling in particular states of the system. Of the American species the Gualac is the most important and is still much used in medicine. The Zygophyllum Fabago is occasionally used as an anthelmintic.
Remarks on Genera and Species. In so far as Indian Botany is concerned there is but little room for remark on this head. I may however observe that the numerous varieties which the Indian plants present seem to afford strong ground for doubting whether all the species referred to each of the two genera are tenable. Oar Tribulus for example has the leaves with from 3 to 8 pairs of leaflets, the carpels with two or four spines often on the same plant, and every degree of clothing from nearly glabrous to densely tomentose, I thence infer that both T. tenestris and T. lanuginosa are identical, and probably several others may be reduced to that species. Fagonia Mysorensis is characterized as having simple not trifolialate leaves. The accompanying figure will show how erroneous that is, and I doubt not the same will be found in several of the others and prove that they all form but one species.
EXPLANATION OF PLATE 64.
    1. Fagonia mysorensis —natural size.
    2. A flower.
    3. The sam?, petals removed and sepals forcibly opened to show the insertions of the stamens and the ovary in situ.
    4. Stamens back and front views.
    5. Ovary cat vertically, ovules erect.
    6. ---transversely, 5-celled, each cell or carpel attached to a central gynojihore.
    7. A fruit —natural size.
    8. The same cut transversely.
    9. A seed.
    10. Divided lengthwise, to show the embryo seated in the base of the large albumen.
    11. Embryo removed —with the exceptions mentioned, all more or less magnified.
ZYGOPHYLLEÆ FAGONIA MYSORENSIS. (Roth.)