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1. UL. nrrioum Nutt. Silicula shining, gla- 
brous; petals whitish ©. Common. Spring. 
2. L.uatrees Hook. Silicula strongly re- 
ticulated; petals greenish. ©. Marin Coun- 
ty. Summer. 
5. Capsella Vent. SHEPHERD’S-PURSE. 
Silicula dorsally compressed, with carinate, 
l-nerved valves and narrow replum. Seeds 
several. Flowers white.—©. 
1. C. Bursa-pastoris L.—Common all the 
year round. 
Ballast weed, introduved from Europe. 
6. Tropidocarpum Hook. 
Siliqua dorsally compressed, linear, with 1- 
nerved, carinate valves, and very narrow re- 
plum. Seedsa. Flowers yellow.—© 
1. TT. gractze Hook.—-Marin county. Sum- 
mer. 
7. Nasturtium R.Br. Warer-Crzss. 
Siliqua linear, with concave valves, and only 
rudimentary nerve. Seeds, 2-seriate in each 
valve.—Aquatic. 
1. N.oFFIcINALE R. Br. Petals white.—2,. 
Common all the year round. 
Introduced from Europe, at present perfectly 
naturalized, 
