THALAMIFLOR.E. 



197 



The affinities of the Order are somewhat complex : the structure of the 

 essential organs allies them closely to the Magnoliaceae and Dilleniacese, 

 the former of which, however, have distinct stipules, while the latter 

 have arillate seeds ; and both differ in habit. Some genera are closely 

 related to the Berberidacere, from which, however, they differ in the 

 indefinite stamens and in the sutural (not valvular) dehiscence of the 

 anthers. From Nymphseaceae and Papaveracese, which they resemble in 

 certain respects, they are distinguished by their distinct carpels, and in 

 the case of the Poppies by their watery (not milky) juice. Relations 

 exist also with some Calycifloree. as with Rosaceaa, from which the present 

 Order is known by its hypogynous stamens, the abundant peiisperm of the 

 seeds, and the general proper- p- g^. 



ties. Sheathing bases of the 

 leaves, resembling adnate sti- 

 pules, occur here and in Um- 

 belliferce, and they somewhat 

 resemble the stipules of Rosa. 

 A kind of representation of 

 this Order occurs among the 

 Monocotyledons, in Alisma- 

 cea3, where the free carpels 

 and the habit give a resem- 

 blance to those Ranunculacese 

 which have a ternary calyx. 

 The Preonies approach the 

 Nymphaeacese in the disk, 

 wnich is remarkably deve- 

 loped in P. Moutan, almost 

 entirely enclosing the carpels ; 

 the stamens of Paeonies are, 

 owing to a slight excavation 

 of the receptacle, perigynous 

 rather than hypogynous. 



Number and Distribution. 



This Order contains from 

 30 to 40 genera and five or 

 six hundred species, which 

 latter are most abundant in 

 damp, cool climates, and are 

 scarcely met with in the 

 tropics, except on mountains. 



Qualities and Uses. The 

 plants of this Order generally 

 possess acrid and more or 

 less narcotic-acrid properties, 

 some being virulent poisons. 

 The poisonous property re- 

 sides in the watery juice, and 

 is in most cases volatile, and 



capable of dissipation by heat, AconUum 



or even simple drying, and by infusion in water. It appears to be 



