LEGUMIN0S2E-PAPILI0NACEJE. 



227 



little lateral bractlets, themselves rarely persistent. Some sixty 

 species of Tounatea are known, 1 grouped by the most recent authors 

 into five sections 2 based on the form and dehiscence of the calyx, the 

 form of the vexillary petal, and that of the stamens, especially as 

 regards the anthers. 



Near Tounatea have been placed four genera, distinguished from 

 it chiefly by the following characters. Aldina (figs. 205, :2()C) has 

 the flowers of Tounatea, but with a nearly regular corolla of five or 

 six segments. Hence it might perhaps be better to take this genus 

 rather than Tounatea as the type of the section ; its receptacle is 



Aldina lalifolia. 



Fig. 205. 

 Flower. 



Fig. 206. 

 Longitudinal section of flower. 



also nearly regular, cup-shaped, and lined by a thick disk, external 

 to which are inserted the pieces of the perianth and androceum. 

 Zollemia has also nearly regular flowers (figs. 207, 208), with five 

 equal or nearly equal petals, and from nine to fifteen stamens. The 

 flower-buds are elongate and acuminate. The leaves are reduced to 

 a single leaflet. The depth of the receptacle, too, is reduced, so that 

 the insertion of the perianth and androceum becomes nearly 

 hypogynous. Exostyles has nearly the flower of Zollernia, but with 



1 Velloz., Fl. Fhim., xi. t. 17, IS, 19 (?), 22, 

 23 {Mimosa).— Vaiil., Ic. Amer., t. 9; Eel. 

 Amer., t. 20 ; Symb., t. 34. — Desvx., in Arm. 

 <S'c. Nat., ser. 1, ix. 424.— DC, Mem. Ligvm., 

 t. 58-60.—- Deless., Icon. Sel., iii. 42, t. 71.— 



Bentii., in ITooJc. Joum., ii. 87. — W \: p., l'< j>. 

 i. 841; v. 563; Ann., ii. 446. 



' 2 1. Cyalhostegia (BENTH.) : 2. Dithyria 

 (Benth.)j 3. Eutounatea; i. Vossira; 5. /'>• 

 tuloides (see below, Gen., a. 289). 



Q •- 



