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cation disposed with the utmost symmetry ; and Detarium, instead of a legume, 

 bears a fruit not distinguishable from a drupe. This last circumstance is 

 easily to be understood, if we bear in mind that a legume and a drupe differ 

 more in name than reality, the latter being formed upon precisely the same 

 plan as the former, but with this modification, that its pericarpium is thickened, 

 more or less fleshy on the outside and stony on the inside, 1-seeded, and inde- 

 hiscent. Hence some of the regular-flowered genera with distinct stamens may 

 be said to be Rosaceous in flower, and Leguminous in fruit. Simple, there- 

 fore, as the diagnosis of the order usually is, Mr. Brown is perfectly correct in 

 asserting that, until he indicated the difference of the position of the odd lobe 

 of the calyx in Leguminosa? and Rosacese (Amygdaleas), no positive character 

 had been discovered to distinguish the one order from the other. The presence 

 of stipule at the base of the leaflets of the compound leaves of Leguminosse 

 is a character in the vegetation by which they may be known from Rosaceae. 

 Myroxylon agrees with Samydea; in the remarkable glandular marking of the 

 leaves, in which the pellucid spaces are both round and linear — a very singular 

 and uncommon character, which was first pointed out by Mr. Brown. Congo 

 444. Very few double flowers are known in this order : those of Spartium 

 junceum and Ulex europreus are the most remarkable : the nature of the latter 

 I have described in detail in the Trans, of the Hort. Soc. vol. 7. p. 237. Two 

 ovaria are common in Wisteria sinensis ; and the same phenomenon is to be 

 seen, according to Decandolle, in Gleditschia : it appears also to be normal in 

 Diphaca and Cresalpinia digyna. M. Aug. St. Hilaire is said (Dec. Mem. 52) 

 to have found a Mimosa in Brazil with 5 carpella : on account of these, and 

 other circumstances, M. Decandolle assumes the carpellum of Leguminosee to 

 be solitary by abortion, and that a whorl of 5 is that which is necessary to 

 complete the symmetry of the flowers. Of the accuracy of this view I am sa- 

 tisfied ; but I think it might have been proved as satisfactorily from analogy, 

 without the aid of such instances. In consequence of the highly irritable 

 nature of the leaves of many of the plants of this order, and of the tendency 

 to irritability discoverable in them all, some botanists have placed them at the 

 extremity of their system, in contact with the limits of the animal kingdom. 

 See Jlgardh Classes, p. 4, and Martins, H. R. M. p. 176. For observations 

 upon the nature of this irritability, see Diitrochet sur la Motility, Paris, 1824, 

 in which the author endeavors to show that the motion is the effect of galvanic 

 agency ; and the same writer's JYouvelles RechercJies sur V Exosmose, <£c, in 

 which he alters the explanation of the manner in which galvanism produces 

 the motion, adhering, however, to his opinion of that subtle principle being the 

 real agent. This ingenious naturalist might have been satisfied with attri- 

 buting the phenomenon to an inherent vital action, without puzzling himself with 

 a vain search after first causes, which always leaves the most successful inquirei 

 exactly where he set out. For remarks upon the order in general, see M. De- 

 candolle's valuable Memoire, published in Paris in 1825-6, in one thick 

 volume 4 to. The relation that is borne by this order to Chrysobalaneas and 

 Amygdalere has been already explained under those orders. To the tribes for- 

 merly included under the name of Terebintacere, Leguminosaj are nearly allied 

 in many important circumstances, but are distinguished by their stipules, which 

 nevertheless exist in Canarium among Burseraceee, and which do not exist in 

 Sophora, a genuine, and Myrospermum, a spurious Leguminous genus. The 

 affinity of the latter to Amyridea? is, however, so great, that it appears to me 

 very questionable whether it ought not to be absolutely referred to that order 

 rather than to Leguminosae. With Xanthoxyleae they are allied through 

 Ailanthus. The monadelphous stamens, irregular flowers, occasional simple 

 ovarium, style, and stigma of Polygaleae, are all so many points of affinity 

 with Le/niminosae. 



