MUSTARD FAMILY. 



43 



Pod terminating in a strong beak. Seeds round. Flowers 

 yellow. 



Calyx erect in blossom. 4. Beassica. 



Calyx spreading in blossom. 5. Sinapis. 

 Pod sliort, not many times longer than wide (silicle or pouch). 

 Pod globose (rarely forming). Flowers white. Leaves 



mostly undivided. 6. ARMORAaA. 



Pod pear-shaped, many-seeded. Flowers yellow. 7. Camelina. 

 Pod flattened contrary to the narrow partition. 



Pod triangular obovate. Seeds many. 8. Capsella. 



Pod roundish, small. Seeds 2. 9. Lepiditui. 

 ^ 2. Pod not separating into valves but breaking up into joints when 

 ripe. 



Flowers yellow or purplish. 10. Rathanus. 



1. NASTTJR'TIUM, R. Br. Water-cress. 



[Latin, Xasus tortus, a tortured nose, from the pungent effect of the plant.] 



Silique, nearly terete, sometimes almost as sliort as a silicle, usually 

 curved upwards ; valves nerveless. Seeds small, irregularly disposed in 

 a double series, not margined. Aquatic or subaquatic herhs. Leaves 

 often piunately dissected. 



1. N. officinale, R. Br. Leaves pinnately divided ; segments rounded 

 or oblong ; petals white, twice the length of the calyx. 

 Officinal Nasturtium. "Water-cress. 



Fr. Cresson de Fontaine. Germ. Die Brunnenkresse. Span. Berro. 



Perennial. Stem 6-12 and 18 inches long, branching. Leaves odd-pinnately dissected 

 segments in 3-4 pairs, the terminal one largest. Petals white. 

 Brooks and rivulets : probably introduced from Europe. Fl. June. Fr. July. 



Obs. This plant (well known as the " Water Cress" in England,) is 

 frequently cultivated, and is naturalized in some places; It affords an 

 excellent and wholesome salad, antiscorbutic in its properties, as all the 

 CrucifercE are, and being easily propagated, is worthy of being introduced 

 into all suitable localities. 



2. BARBARE'A, R. Br. Winter-cress. 



[So named from having been formerly dedicated to St. Barbara.] 



Silique linear, somewhat 4-sided, the valves keeled by a mid-nerve. 

 Seeds in a single series. Leaves lyrately pinnatifid. 

 1. B. PR^'cox, R. Br. Lower leaves lyrate, the terminal lobe obovate, 

 or rounded, coarsely sinuate-dentate ; upper leaves pinnatifid, with 

 entire linear -oblong segments ; siliques linear, elongated, scarcely thicker 

 than their pedicels. 



Early Barb are a. Scurvy-grass. Early Winter-cress. 



Fr. Roquette des Jardins. Germ. Die Winter-kresse. Span. Yerba 

 de Santa Barbara. 



i?ooi biennial ? Stem 9-15 inches high, somewhat branching. Leaves smooth; lowef 

 ones 3-4 inches long. Petals yellow. *S'i7iq'ites 2-3 inches long, slender. 

 Gardens : cultivated. Fl. May -June. Fr. July -Aug. 



