156 ON SEEDLINGS 



tion, but becoming emarginate and more elongated at the Base by 

 subsequent growth, petiolate, glabrous, with the exception of a few 

 scattered hairs on the petiole, light green above, paler beneath, 

 trinerved at the base, with two other lateral nerves arising from 

 the midrib below the middle of the lamina, describing a curve round 

 an oval space and again uniting with the midrib close to the apical 

 notch ; lamina 6-8 mm. long, 4-5-5 mm. wide ; petiole slightly 

 channelled above, convex on the back, 7'5-9 mm. long. 



A few terminal pores or water-stomata are found at the apex of 

 the midrib. 



Stem annual, and developed when about to flower ; primary 

 internodes undeveloped. 



Leaves simple, radical (ultimately cauline), exstipulate, petio- 

 late, coarsely hairy, alternately and ascendingly penninerved, ulti- 

 mately runcinately pinnatifid and pinnatisect ; petioles semiterete, 

 channelled above, dilated and clasping at the base, more or less 

 hairy. 



No. 1. Rotund, obtuse, obscurely dentate or crenate, slightly 

 cuneate at the base. 



No. 2. Similar but more deeply dentate-crenate and often lobu- 

 late at the base. 



No. 3. Runcinately pinnatisect with three to five lobes ; lateral 

 lobes small, oblong, obtuse, entire or dentate ; terminal lobe much 

 the largest, rotund, coarsely and deeply dentate with glandular 

 mucronate teeth. 



Sisymbrium runcinatum, Lag. (fig. 164). 



Boot and hypocotyl as in preceding species. 



Cotyledons small, glabrous ; lamina oblong, obtuse, 4 mm. long, 

 2 mm. broad ; petiole 3-5 mm. long. 



Stem as in Hesperis matronalis. 



Leaves hairy, especially when young and on the petioles, ulti- 

 mately glabrescent ; petioles flattened above, convex beneath, slightly 

 dilated at the base. 



No. 1. Small, broadly ovate, obtuse, almost or quite entire. 



No. 2. Oblong, sublobulate ; lobes rounded. 



Nos. 3 and 4. Similar but larger. 



No. 5. Oblong, pinnatifid ; terminal lobe triangular-hastate, with 

 a very obtuse apex and side lobes. 



No. 6. Pinnatind with obtuse lobes ; terminal one triangular 

 obtuse. 



Nos. 7-10. Runcinate, pinnatifid ; lateral lobes broadly ovate, 

 or triangular obtuse, or rounded at the end, alternate, spreading at 



