Yellow to Orange Flowers 323 



racemes. Fruit: the siliques elongated, sessile, tipped with a flattened 

 conic beak. Not indigenous. 



A handsome species bearing showy yellow flowers in ter- 

 minal racemes, and having large oval leaves that are very 

 coarsely toothed, rough to the touch, and conspicuously 

 veined. The basal leaves are lobed. Like all the Mus- 

 tards, it has four cruciform petals. This is an introduced 

 plant. 



HARTWEG'S TANSY MUSTARD 

 Sisymbrium Hartwegianum. Mustard Family 



Stems: slender. Leaves: pinnate; leaflets lanceolate, obtuse and 

 acutely toothed. Flowers: small, yellow. Fruit: the siliques erect on 

 ascending pedicels, linear, elongated. 



A coarse uninteresting plant, with pinnately cut leaves, 

 the tiny leaflets being sharply toothed. The flowers are 

 small and yellow and the pods long and narrow. 



Sisymbrium altissimum, or Tall Hedge Mustard, has tall 

 freely-branching stems and lower leaves which are runci- 

 nate-pinnatifid, the narrow lobes often auriculate, and 

 smaller, very deeply cut upper leaves. The pale yellow 

 flowers are inconspicuous. The pods are rigid, very long, 

 divergent and hardly thicker than the short pedicels. This 

 is an introduced plant. 



Sisymbrium canescens, or Pale Tansy Mustard, is a soft- 

 hairy species with long deeply cut leaves growing out almost 

 at right angles from the stem; very small yellowish flowers 

 and pods in long racemes. 



Sisymbrium incisum, or Western Tansy Mustard, is a 

 similar plant to the Pale Tansy Mustard, but is greener and 

 less hairy, and has longer more slender pods and one-ranked 

 seeds. The leaves have not such a fringed appearance as 

 those of Sis\mbrium canescens. 



