SECT. II 



PHANEROGAMIA 



625 



consiHcuous, reddish-yellow anthers (Fig. 644). Tlie fruit is very peculiar. The 

 ovary has a long stalk and bears two ovules near the tip. One of these develops 

 into the seed of the indehiscent, compressed pod, which has a broad wing 

 along the ventral suture and a narrower wing along the dorsal suture (Fig. 645). 

 The bell-shaped calyx persists on the stalk. — 3. Gcnistcae. All ten stamens are 

 coherent (Fig. 641 B). Leaves pinnate or simple, margin entire. Genista, Saro- 

 tJiamnus, Lupinus, Cytisus (Fig. 

 646). The Laburnum (CijtisKS 

 Lahicrnum) is one of the com- 

 monest ornamental trees of our 

 gardens and grows wild in the 

 Alps. It has tripinnate leaves 

 and long pendulous racemes 

 of yellow flowers. C. Adami, 

 which is found occasionally in 

 gardens, was supposed to have 

 arisen by the grafting of C. 

 purpureus on G. Laburnum. 

 The racemes and flowers of 

 one and the same individual 

 sometimes resemble the former 

 and less commonly the latter 

 ancestral form (Fig. 221). The 

 intermediate form is however 

 usually sterile. Ulex, Furze, 

 a characteristic British plant. 

 Spartium, distributed in the 

 Mediterranean region. — 4. Tri- 

 folieac. Leaves trifoliate, ser- 

 rate. Flowers aggregated in 

 heads or in spikes or umbels. 

 Stamens (9) -Hi. Indehiscent 

 fruits. Trifolium, Clover, with 

 persistent calyx and corolla. 

 Mcdicago, Medick, with de- 

 ciduous corolla ; fruit sickle- 

 shaped or spirally twisted. 

 Melilotus, Melilot, with race- 

 mose inflorescences. Tri- 

 (jonclla. Ononis, Rest-Harrow. 

 The increase in the amount of 

 nitrogen in the soil effected by 

 the root -tubercles (cf. p. 231, 

 Figs. 201, 202), of Leguminosae 

 finds its practical application in European agriculture in the cultivation of species of 

 Trifolium, Medicayo and Liqnnus. — 5. Loteac. Lotus Bird's-foot Trefoil (Fig. 642). 

 Leaves imparipinnate, lowest pair of leaflets owing to the absence of the petiole 

 resembling stipules. Anthyllis, Kidney-Vetch. Tetracjonolohus. — 6. Galeyeae or 

 Astragalcae. Leaves imparijiinnate ; a very large sub-family, the plants belonging 

 to which show much diversity in habit. In species of Astragalus (^"), which are 

 low shrubs of the eastern Mediterranean region and of western Asia, the rhachis of 

 the leaf persists as a sharply pointed thorn for years after the leaflets have fallen. 



2s 



Fig. 647. — Astragalus gummifcr. (| iiat. size. After 

 A. Meyer and Schumann.) Official. 



