CRUCIFEIUE. 13 



* * Pod a silicic (comparatively short). 

 *- Silicle compressed parallel with the broad partition, or globular. 



8. Draba. Flowers white. Pod flat, tioiated when ripe, many-seeded. Coty- 



ledons accumbent. 



9. Alys'sum. Flowers pale yellow or white. Pod orbicular, flat, 2-4-seeded. 



10. Camel'ina. Flowers yellow. Pod pear-shaped, pointed, valves 1-nerved. 



Cotyledons incumbent. 



-i- -- Silicle compressed contrary to the narrow partition. 



11. CapseMa. Flowers white. Pod obcordate-triangular, valves boat-shaped, 



wingless. Seeds numerous. Cotyledons incumbent. 



12. Tlilas'pi. Flowers white. Pod obovate or obcordate, winged. Seeds 



several. Cotyledons accumbent. 



13. L,epid'ium. Flowers white or whitish. Pod roundish, very flat, the 



valves boat-shaped and winged. Seeds solitary. 



-- -i- -*- Silicle fleshy, jointed. 



14. Caki'le. Flowers purplish. Pod 2-jointed, fleshy. Leaves fleshy. Co- 



tyledons accumbent. 



1. NASTUR'TIUM, R. Br. WATER-CRESS. 



1. N. officinale, R. Br. (WATER CRESS.) Flowers white. 

 Stem spreading and rooting. Leaves pinnate; leaflets 3-11, 

 roundish or oblong, nearly entire. Pods oblong-linear. Ditches 

 and streamlets. 



2. N. palustre, DC. (MARSH CRESS.) Flowers yellow. 

 Stem erect. Leaves pinnately parted, the lobes cut-toothed. 

 Pods ovoid. Wet places. 



3. N. lacus'tre, Gray. (LAKE CRESS.) Flowers white. An 

 aquatic plant, with the submerged leaves finely dissected ; the 

 leaves out of the water oblong, and either entire, serrate, or 

 pinnatifid. Pods ovoid, 1-celled. 



4. N. Armora'cia, Fries. (HORSERADISH.) Has escaped 

 from gardens in many places. Flowers white. Root-leaves very 

 large, oblong, and generally crenate ; stem-leaves lanceolate. 

 Pods globular. Roots very large. 



. DENTA'RIA, L. TOOTHWORT. PEPPER-BOOT. 



1. D. diphyTla, L. (TWO-LEAVED T.) Flowers white. Stem- 

 leaves 2 y nearly opposite, ternately divided. Root-stock toothed, 

 pleasantly pungent to the taste. Rich woods. 



2. D. lacinia'ta, Muhl. (LACIXIATE T.) Flowers purplish. 

 Stem-leaves 3 in a, whorl. Root-stock jointed, scarcely toothed. 

 Along streams. 



