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Page:Illustrations of Indian Botany, Vol. 1.djvu/80

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ILLUSTRATIONS OF INDIAN BOTANY.

provinces, and that a very doubtful native ; as there appears to be no Tamul or Telogoo name for it. I have however thought it right to introduce it here, as forming a link in the chain of affinities, which it is desirable should remain as much unbroken as the Flora will permit. The only species yet known, in this part of India, is found in corn fields on the Neilgherries, where it was probably brought, with corn seed, either from Bengal or Europe.

The Fumariaceae are glabrous, herbacious, tender plants; with watery juice; either annual or perennial; occasionally with tuberous roots, and alternate, generally, much divided, ex-stipulate leaves; often furnished with tendrils ; and irregular, hermaphrodite, spiked, bractiolate flowers.

The calyx consists of 2 small sepals : the corolla of 4 petals cruciately placed, one or both of the outer ones saccate at the base, the inner ones callous below and coloured at the apex, where they cohere and inclose the anthers and stigma. The stamens are united in two parcels, and placed opposite the outer petals, each parcel composed of a centre perfect, two-celled anther, and 2 one-celled, imperfect or half, anthers; very rarely all separate. Ovary superior one-celled, ovules horizontal. Style filiform, Stigma with two or more points. Fruit dehiscent or indehiscent, either a one or two-seeded nut, or a succulent, many-seeded, pod. Seeds horizontal shining, cristed. Albumen fleshy. Embryo, nearly straight, out of the axis.

Affinities. Most Botanists consider Fumariacece as very nearly allied to Papaveracece on account of their two-leaved deciduous calyx, the structure of the fruit of the dehiscent species, and their fleshy albumen ; but differing in their watery juice, their irregular petals, and their diadelphous stamens, with indifferently one or two-celled anthers. Dr. Lindley however proposes a different and very ingenious exposition of their structure, Avhich I shall quote in his own words, and which will be easily understood on comparing his description with the magnified figures in the plate. After referring to the above exposition of their structure, he proceeds. "I am, however, inclined to suspect that the floral envelopes of Fumariacece are not rightly described. I am by no means sure that it would not be more consonant to analogy to consider the parts of their flower divided upon a binary plan; thus understanding the outer series of the supposed petals as calyx, and the inner only as petals; while the parts now called sepals are perhaps more analogous to bracts; an idea which their arrangement, and the constant tendency of the outer series to become saccate at the base, which is not uncommon in the calyx of Cruciacece, but never happens, as far as I know, in their petals, would seem to confirm. Of this, some further evidence may be found in the stamens. Those organs are combined in two parcels, one of which is opposite each of the divisions of the outer series, and consists of one perfect two-celled anther in the middle, and two lateral one-celled ones : now, supposing the lateral one-celled anthers of each parcel to belong to a common stamen, the filament of which is split by the separation of the two parcels, an hypothesis to which I do not think any objection can be entertained, we shall find that the number of stamens of Fumariacece is 4, one of which is before each of the divisions of the flower; an arrangement which is precisely what we should expect to find in a normal flower, consisting of 2 sepals and 2 petals, and the reverse of what ought to occur, if the divisions of the flower were really all petals, as has been hitherto believed."

The following extract also from Dr. Lindley's work, exhibiting a beautiful instance of design, observable in all the works of nature when properly studied, is too interesting to be passed over.

"The economy of the sexual organs of Fumariacece is remarkable. The stamens are in two parcels, the anthers of which are a little higher than the stigma; the two middle ones of these anthers are turned outwards, and do not appear to be capable of communicating their pollen to the stigma; the four lateral ones are also naturally turned outwards; but by a twist of their filament their face is presented to the stigma. They are all held firmly together by the cohesion of the tips of the flower, which, never unclosing, offer no apparent means of the pollen being disturbed, so as to shed upon the stigmatic surface. To remedy this inconvenience, the stigma is furnished with two blunt horns, one of which is inserted between and under the cells of the anthers of each parcel, so that without any alteration of position on the part of either organ, the mere contraction of the valves of the anthers is sufficient to shed the pollen upon that spot, where it is required to perform the office of fecundation."