.ILLUSTRATIONS OF INDIAN BOTANY. I77 



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Character of the Order. Flowers irregular. Calyx free, persistent, 4-5-sepaled ; 

 sepals cohering into a 4-5-cleft calyx, or united by pairs. Corolla monopetalons, hypogynous, 

 pentamerous or, by union of the upper pairs, tetramerous, persistent ; aestivation imbricated ; 

 tube more or less curved; limb more or less 2-lipped. Stamens 4, didynamous, inserted on 

 the tube of the corolla ; anthers 2-celIed, persistent, with the cells often cuspidato-calcarate at 

 the base, dehiscing by a longitudinal slit or oblong pore. Ovary free, bound at the base by a 

 fleshy disk, one-celled ; placenta parietal paired on each side the ovary, either distinct or 



feminately-connate, or with two broadly two-lobed placentae extending from the parietes. 

 lacents lateral as regards the axis of inflorescence. Ovules usually numerous, anatropous, 

 with sometimes a longish funiculus; style terminal, simple; stigma large, capitato-two- 

 lobed ; lobes either over the placentae, or placed anterior and posterior, sometimes obscurely 

 sulcated in the middle, rarely sub-clavate, undivided. Capsule 1-celled, two valved at the apex 

 or through its whole length ; valves bearing on the middle or oftener towards the middle, solitary 

 or paired, filiform or broad placentas. Seed numerous, rarely few, minute, globose, oblong, or 

 pear-shaped ; testa thick, spongy, scrobiculate or tubercled ; albumen copious ; embryo minute, 

 obovoid. — Herbaceous, leafless plants, growing parasitically on the roots of other plants, often 

 forming dense masses of great extent round the base of plants suited for their support; stems 



erect more or less covered with brown, yellowish, or colourless scales, in place of leaves. 



Affinities. In my introductory remarks I have to some extent anticipated what I have 



to say here. Lindley maintains "that there can be little doubt that the nearest afKnity 

 of OrohanchacecB is to Gentianacece with some of which, as for example Voyria^ they correspond 

 in their leafless habit and moreover in their corolla, adhering firmly to the base of the fruit, 

 which it covers when ripe." These points of agreement however scarcely deserve the name of 

 affinities they are rather analogies or resemblances. He continues "The great points of resem- 

 blance between Orobanchacece and GesneracecE and Scrophularacete consists in their monopeta- 

 lous, didynamous flowers and bicarpillary, polyspermous fruit ; and it is these that have led to the 

 opinion that all the orders are closely allied. Such marks of agreement are doubtless important 

 but they may be over balanced by others of greater importance. One of these is the position of 

 the carpels with respect to the axis of inflorescence. In the whole category of plants, forming 

 the Bignonal alliance, the carpels stand fore and aft with respect to the axis, while in Gentian- 

 worts we have as universally the two carpels placed laterally. In this striking character Orohan- 

 che agrees with the latter.'' Somewhat further on he states that he considers "that their capsule 

 (of Orobanchaceae) consists of two carpels standing right and left of the axis of inflorescence, and 

 the margins not inflexed in the form of dissepiments, is incontestable," and that they bear the 

 placentae on their axis, that is, directly under or continuous with the lobes of the stigma, not, in 

 the usual position, alternate with them. 



Mr. Brown dissents from these views on the ground that the placentae of OrobanchacecB 

 are double, and that he believes the carpels are anterior and posterior, not lateral, as stated 

 hy Lindley. As, however, his diction is not susceptible of abridgment, I must quote the 

 ^hole paragraph though rather long. The previous remarks to which he alludes, as apper- 

 taining to the first family, refer to Orchidece. 



*'With regard to the second family, In which Mr, Lindley believes the disk of the carpel to 

 he ovuliferous, namely, Orobanchece, I find no other argument advanced in support of this view 

 than that derived from the bursting of the capsule into two lateral valves : but an opinion 

 founded on dehiscence only, may be said to be a mere begging of the question ; division through 

 the axis of carpels, especially in the families related to Orobanchece, being nearly as common as 

 separation of their margins. In this family also, as in Orchidece, the placentae are double, 

 an argument in favour of their sub-marginal origin : and although, whether the carpels be regarded 

 as lateral, or anterior and posterior, the placentae are not strictly marginal, yet there are 

 other families where a similar position of placentae is found, but in which the structure assumed 

 in this hypothesis has never been suspected. As to the supposed affinity o£ Orobanchece with 

 Gentiaiiece, which might be adduced in support of this view, as far as it is founded on tbe 



assumed aoTeement nf thft twrn or<!flrs in the lateral position of 



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