87 



In many respects this order is one of the most important which the botanist 

 can study, but especially as it serves to show how little real importance ought 

 to be attached to dehiscence of fruit in determining the limits of natural orders. 

 What may be called the normal fruit of Leguminosae is a legume, that is to 

 say, a dry simple ovarium, with a suture running along both its margins, so 

 that at maturity it separates through the middle of each suture into two valves; 

 but every conceivable degree of deviation from this type occurs : the Arachis 

 and many more are indehiscent ; Detarium is drupaceous ; in Charmichaelia 

 the valves separate from the suture, which remains entire, like the replum of 

 Cruciferae ; in all Lomentaceous genera, such as Ornithopus, the valves are 

 indehiscent in the line of the suture, but separate transversely; in Entada a 

 combination of the peculiarities of Carmichaelia and Lomentaceas occurs ; and, 

 finally, in Haematoxylon the valves adhere by the suture and split along the 

 axis. The divisions which have been proposed in this extensive order are of 

 unequal value ; it is possible that two of them, namely, Mimosas and Caesalpi- 

 nieae may deserve, as Mr. Brown seems to think, the rank of independent 

 orders ; for they really appear to be of the same importance with reference to 

 Papilionaceae, as Amygdaleae and Pomaceae are with respect to Rosaceae, or 

 as Amyrideae, Connaraceae, Anacardiaceae, and Burseraceae, with respect to 

 each other. I give them, however, as I find them in Decandolle. 



His first and most important division depends upon the form of the embryo, 

 out of which arise the divisions called Curvembriae and Rectembriae ; viz. 



CURVEMBRIJE. 



Radicle bent back upon the cotyledons. 



These are distinguished into two tribes by the structure of their flowers, 

 viz. 



Tribe 1. Swartzieje. 



Calyx bladdery, with indistinct lobes. Stamens hypogynous. Corolla none, 

 or petals only 1 or 2. 



Examples. Swartzia, Baphia. 



Tribe 2. Papilionaceae. 



Calyx with distinct lobes. Stamens perigynous. Corolla papilionaceous. 



Examples. Vicia, Pisum, Sophora. 



The germination of this tribe varies thus : — some of the species push their 

 cotyledons above ground, which become green, resembling leaves ; arid of these 

 none bear seeds which are eaten by man or animals ; others germinate with 

 their cotyledons under ground, and it is among these only that all the kinds 

 which bear what we call pulse are found ; the former Decandolle calls Phyllo- 

 lobece, and they are divided by him into sections, viz. 1. § Sophoreae, 2. § Lo- 

 teae, 3. § Hedysarea? ; the latter he designates as Sarcolobece, which compre- 

 hend, 4. § Vicieae, 5. § Phaseoleae, 6. § Dalbergiese. 



RECTEMBRIJE. 



Radicle of the embryo straight. 



The tribes are known by the position of their stamens and the aestivation of 

 their petals. 



Tribe 3. Mimose^e. 



Sepals and petals valvate in aestivation. Stamens hypogynous. 

 Examples. Acacia, Mimosa, Inga. 



Tribe 4. CjesalpiniejE. 



Petals imbricated in aestivation, and stamens perigynous. 

 Examples. Arachis, Ceesalpinia, Cassia. 



