76 VEGETABLE ORGANOGRAPHY. 



It is, then, from this zone, situated below the ovary, that 

 the petals and stamens proceed ; we call them Hypo- 

 gynous, and the plants which have this organization 

 Thalamiflor^e. In this case all the principal organs 

 of the flower, — the calyx, the ovary, and the productions 

 of the torus, are necessarily distinct and not adhering 

 together. But it frequently happens that the torus 

 extends either inwardly upon the pistil or its support, 

 or outwardly upon the calyx, or upon both at once, and 

 it contracts an intimate adhesion either with one or both 

 of these organs. Let us follow the details and the conse- 

 quences of these adhesions of the torus. 



In a great number of the Leguminosse the torus is 

 prolonged around a very slender pedicel, which supports 

 the ovary, and forms a kind of small sheath, sometimes very 

 short, as in Peraltea, sometimes as long as the pedicel, 

 and reaching the base of the ovary in Neurocarpi/m 

 ellipticum and Martiusia. In several Capparideas the 

 torus is prolonged, and intimately surrounds the support 

 of the fruit, — for example, in Gynandropsis, — and the 

 stamens arise above this sheath. In the Aurantiaceae, 

 the torus, which is thick and glandular, is prolonged and 

 intimately applied to the verticillate and membranous 

 carpels of these plants, and increasing with the fruit 

 forms the glandular, yellow, and valveless envelope 

 which incloses the carpels. The same thing occurs in 

 the Poppy, except that the prolongation of the torus is 

 thin, strongly adherent, and does not reach entirely to 

 the top of the carpels, so that at their maturity they open 

 at the apex. It is the same in the fruit of Nuphar ; and 

 we see that these examples only differ from that of 

 Pceonia Moutan, above mentioned, in that the prolonga- 

 tion of the torus does not adhere to the carpels in this 

 Pasony, whilst it does so in the Poppy and Nuphar. 

 The torus of Nymphcea presents another peculiarity — 



