TETRAD YNAMIA SILIQUOSA. 145 



3. N. terrestre, leaves pinnatifid, unequally toothed ; root ta- 

 pering ; flowers yellow, the petals scarcely so long as the calyx 5 

 pod curved. Annual Yellow Cress. 



Hob. Watery places. About Ladykirk and Norham, Mr 

 W. Baird. Sides of the Tweed from West Ord to Nor- 

 ham, plentiful. In the pond below Calf-hill ; and at the 

 Cow-port. June, July. 



The root is simple and spindle-shaped ; but in a specimen, 

 which measured upwards of two feet in height, we found 

 it a dense bunch of fibres. The stem is frequently pur- 

 plish, as are also the leaves, which are occasionally some- 

 what bristly on the margins. Pods short, cylindrical, 

 thick, on patent curved stalks longer than themselves, 

 tipped with a short style crowned with a peltate stigma. 

 The plant rarely exceeds a foot in height, and is often 

 much less. 



201. SISYMB11IUM. 



1. S. offieinale, stem rough with reflexed bristles ; leaves run- 

 cinate, hairy ; flowers small, pale yellow ; pods pressed close to 

 the main stalk, awl-shaped, downy. Common Hedge-mustard. 



Hob. Wastes and road-sides. June, July. 



2. S. IriO) leaves runcinate, toothed, smooth as well as the 

 stem ; flowers yellow ; pods erect, long, slender. London Rocket. 



Hab. On the walls of Berwick-upon-Tweed, Ray. Most 

 abundant at the Pier-gate. July, Aug. 



3. S. Sophia^ leaves doubly pinnatifid, a little hairy ; flowers 

 small, greenish-yellow, the petals smaller than the calyx. Flix- 

 weed. 



Hob. Waste ground near villages. About East-Ord, Etall, 

 and Bamborough, Thomp. July Sept. 



202. BARBAREA. 



1. B. vulganS) smooth ; lower leaves lyrate, the terminal lobe 

 roundish ; upper obovate, toothed ; flowers yellow ; pods an inch 

 long. Yellow Rocket. 



Hab. Sides of the Tweed and Whiteadder ; also at hedge 

 bottoms in moist situations, frequent. A double flowered 

 variety is common in gardens. May Aug. 11 



G 



