Nasturtium CRUCIFERyE 237 



some of which are sometimes abortive (only 2-4 in Lepidiiim, 

 4 in Cardamine hirsuta). Ovary of 2 carpels, 1 -celled with 1 or 2 

 parietal placentas, or rarely one basilar. Fruit a narrow 

 2-valved capsule with 2 parietal placentas, from which the valves 

 separate in dehiscence {fsiliqua) ; if the length does not more than 

 twice or thrice surpass the breadth, the fruit is called a silicula ; 

 usually a false partition is stretched across between the two 

 placentas, rendering the pod 2-celled. In Coronopus the silicula 

 is indehiscent. In Cakile the fruit is indehiscent and trans- 

 versely 2-jointed. Embryo without endosperm. Cotyledons 

 folded so that the back of one is laid against the radicle 

 {incumhent o||), or their edges are longitudinally applied to the 

 radicle (accumbent o=-), or they are folded together lengthwise 

 (condupUcate o). 



Species 1900, dispersed over the whole earth, but chiefly in 

 temperate and frigid zones of the northern hemisphere. 



Fruit a siliqua. 



Seeds in two rows 1. Nasturtmm. 



Seeds in one row. 

 Valves flat, separating elastically and curved back on 



themselves from the base 2. Cardamine. 



Valves convex, not separating elastically. 



[Siliquas adpressed to rhachis, awl-shaped Sisymhrium.'] 



[Siliquas spreading, lanceolate or broadly linear.,.. Brassica.'] 

 Fruit a silicula. 



Silicula dehiscing by valves. 



Silicula obcordate-triangular. Seeds many 3. Capsella. 



Silicula compressed-orbicular. Seeds one in each cell 4. Lepidium. 

 Silicula indehiscent, minute, 1"35 mm. 1., didymous.... 5. Coronopus. 

 Fruit transversely 2-iointed. Plant fleshy 6. Cakile. 



A. Fruit a siliqua with the partition as broad as the valve. 



1. NASTURTIUM Br. 



Branching herbs. Leaves pinnately lobed, pinnatisect or 

 entire. Flowers small, white or yellow. Stamens 6 (or 1-6). 

 Siliqua narrow, valves turgid ; septum hyaline. Seeds small, 

 turgid, in two rows ; cotyledons accumbent. 



Species 50, found almost all over the world. 



N. fontanum Aschers. FL Pruv. Brandenh. 32 (1864); 

 0. E. Schidz in Urh. Symh. Ant. in. 513 ; Urh. Symh. Ant. iv. 257. 

 N. officinale B. Br. in Ait. Hort. Kew. ed. 2, iv. 110(1812); 

 Mac/. Jam. i. 24 ; Griseh. Fl. Br. W. Lid. 13. Cardamine fontana 

 Lam. Encyc. ii. 185 (1786). Sisymbrium Nasturtium-aquaticum 

 L. Sp. PL 657 (1753). N. aquaticum vulgare Sloane Cat. 79 &, 

 Hist. i. 193. Sisymbrium aquaticum ikc. Browne Hist. Jam. 272. 

 (Fig. 98.) Type in Herb, Linn. 



