LEGUMINOSJE-MIMOSEJE. 37 



shorter than in the American species. The gynaeceum is inserted 

 in the very bottom of the cornet at the base of the corolla. In the 

 male flowers it is only a little rudimentary ovary ; in the female or 

 hermaphrodite flowers it is a long sessile ovary, containing numerous 

 descending ovules in two vertical rows, and surmounted by a style, 

 whose stigmatiferous head is somewhat dilated and concave. The 

 fruit is a large compressed pod with very thick woody walls, opening 

 into two valves, which become recurved outwards with considerable 

 elastic force. The seeds, of variable number, are flattened and of irre- 

 gular oval outline ; their coriaceous integuments enclose a compressed 

 fleshy exalbuminous embryo, whose cotyledons are decurrent at the 

 base, enclosing the radicle in a sort of nearly complete sheath. 

 Pentaclethra consists of trees whose alternate bipinnate leaves possess 

 numerous leaflets, with lanceolate stipules and setaceous stipels. 

 The flowers are arranged in ramified spikes. Besides the two species 

 just mentioned, the west of tropical Africa produces a third, recog- 

 nised only as a doubtful member of the genus, namely, P. (?) 

 Griffoniana? 



IV. ACACIA SERIES. 



The Acacias 2 (figs. 28-35) have regular hermaphrodite or poly- 

 gamous flowers. In the former the receptacle may be convex or 

 more or less concave ; it supports a calyx of five, or more rarely four 

 or even three, leaves, cohering to a variable extent and valvate in 

 the bud, rarely reduced to little scales or cilia. The corolla consists 

 of an equal number of valvate petals, free or united for a variable 

 distance. 3 The stamens are indefinite in number, usually very nu- 

 merous, inserted either beneath the gynseceum, or at a certain height 

 above its base, beneath the edges of the receptacular cup ; or even 

 outside a glandular cupule, which lines the cavity of the receptacle 

 and expands more or less beyond it. The filaments are free, or more 

 rarely coherent below for a short distance into one or several bundles. 

 The anthers are two-celled introrse, dehiscing longitudinally.' The 



1 H. Bn., in Adansonia, vi. 205. Gen., n. 6831.— 15. II., Gen., 694, n. 891.— 



2 Acacia T., Instit., G05, t. 375.— Adans., H. 1>n., in Adansonia, iv. 15. 



Font, des Pl.,i\. 319.— J,, Gen., 34G.— Neck., s Either because the corolla is gamopetalous, 



Mem., n. 1297. — Lamk., Diet., i. 8.— W., or through its pieces simply sticking together 



Spec, iv. 1049. — K., Mimos., 7 t. — DC, Prodr., edge l<> edge up to a certain height. 

 ii. 118.— SrACU, Suit, a BuJJ'on, i. 03.— Knol., '* The pollen lias in tins series generally a p< 



