58 viii. cruciferjE (oliveb). [Nasturtium. 



A considerable genus, many species of which are very variable and difficult to define ; 

 occurring in every quarter of the globe, affecting damp or wet situations. 



With a distinct usually branched stem. 

 Leaflets distinct. Racemes short, ebracteate. Pedicels half as long 



or nearly as long as the 9iliqua 1.2V. officinale. 



Leaf-segments confluent or decurrent. Racemes narrow, ebracteate, 



at length elongate. Pedicels many times shorter than the siliqua . 2. 2V T . indtcum. 

 Leaves pinnatipartite ; segments toothed or pinnatifid. Flowers 



(very minute) in the axils of pinnatifid bracts. Pedicels many 



times shorter than the siliqua 3. 2V. cryptanthum. 



Acaulescent or nearly so. 

 Leaves pinnate ; segments petiolulate. Flowers very minute, ebrac- 

 teate. Pedicels many times shorter than the siliqua 4. 2V. humifusum. 



1. N. officinale, Br.; DC. St/st. Veg. ii. 188. Stem branched, often 

 creeping;, floating or ascending to 1-2 ft. or more when luxuriant or sup- 

 ported by other plants. Leaves pinnate ; the upper with 3-7 pairs and a 

 terminal leaflet ; the latter usually larger, varying from roundish to ovate or 

 lanceolate, obtuse, sinuate or dentate. Flowers white ; the petals exceeding 

 the sepals. Siliquas patent or curved upwards, \-~ \ in. long. Seeds in 

 rows. 



Mile Land. Abyssinia, Q. Dillon and Petit {Richard). , 



1 have not seen tropical African specimens, but the species is widely spread through tne 



north temperate zone, occurring in India and at the Cape, probably introduced in some or its 



localities. 



2. N. indicum, Linn. ; DC. Syst. Veg. ii. 199. A branching, glabrous 

 herb, with the upper leaves lyrately-pinnatifid ; segments various, obtusely 

 or acutely toothed or incised. Flowers ebracteate ; racemes at length elon- 

 gate. Siliquas terete, with smooth valves, about |— f in. long, more or less 

 spreading, 4-8 times as long as the short pedicels. — iV. niloticnm, Boiss. 

 Diag. Ser. 1. viii. 19 (2V. Madagascar iense, DC. Syst. Veg. ii. 192 ?). 



Nile Land. Sennar, Kotschy ! Nubia, near Khartoum (Boissier). 

 Lower Guinea. Angola, Dr. Welwitsch ! 



3. N. cryptanthum, Rich. Fl. Abyss, i. 15, A diffuse, ascending or 

 erect, branched, glabrous herb, \-2 ft. high, tough or almost woody below. 

 Upper leaves rather small, not exceeding 1^ in., pinnatipartite, with pinna- 

 tifid, toothed, or entire linear segments. Flowers very minute, white. Siliqua 

 linear or linear-oblong, terete, with thin valves, 4-6 lines long and 4-6 times 

 longer than the short pedicel, shorter than or nearly equalling the bract- 

 Stigma undivided, nearly sessile. 



Nile Land. Abyssinia, Schimper ! Petit ! 



This remarkable plant may be a bracteate form of some other species. 



4. N. humifusum, Gttill. et Perr. Fl. Seneg. 19. A flaccid, nearly 

 acaulescent, glabrous herb (3-8 in. high in our specimens). Leaves thm, 

 pinnate, often interrupted or irregular, segments toothed or sinuate, ° n 

 slender, often winged petiolules ; rachis usually more or less winged near their 

 insertion ; terminal segment usually larger. Flowers very minute, racemose '» 

 racemes ebracteate, shorter than the leaves. Siliquas subterete, on pedicels 

 as long as the fruit is broad, or subsessile; 



