(55 ) 
Nasturtium. —Siliqua linear. Valves 
without nerves. Ovules in each cell a, 
2-seriate. 
Cheiranthus. —Siliqua laterally com- 
pressed. Septum broad. Valves 1- 
nerved. Ovules in each cell 1-seriate. 
Lateral sepals saccate. Petals unguicu- 
late. A 
Caulanthus.—Siliqua terete, valves 1- 
nerved. Ovules in each cell 1-seriate 
Lateral sepals saccate. Petals undulate. 
Streptanthus.—Siliqua laterally com- 
pressed. Valves 1l-nerved. Ovules in 
each cell l-seriate. All sepals equal. 
Petals undulate. 
Barbarea.—Siliqua 4-angular. Valves 
concave, l-nerved. Ovules in each cell 
1-seriate. 
Erysimum.—Siliqua 4-angular. Valves 
‘earinate, 1l-nerved. Ovules in each cell 
1-seriate. 
Tropidocarpum.—Siliqua dorsally com- 
pressed. Valves 1-nerved, carinate. 
Septum very narrow. Ovules in each 
cell 2-seriate. 
Arabis.—Siliqua laterally compressed. 
Valves 1-nerved. Ovules in each cell 
1-seriate. Petals not undulate. 
