148 ON SEEDLINGS 



Ultimate leaves narrowly lanceolate, cuspidately acute, narrowed 

 to a rather broad petiole, subcarinate on the back, with a pro- 

 minent midrib and alternate lateral nerves ascending along the 

 leaf for some considerable distance and uniting, each with the one 

 next above it ; white or hoary, especially beneath, with a closely 

 adpressed pubescence of the characteristic forked hairs. 



Arabis Turczaninowii, Ledeb, 



Primary root tapering downwards with fibrous lateral rootlets. 



Hypocotyl erect, terete, glabrous, almost colourless, 5-10 mm. 

 long. 



Cotyledons oval-oblong, emarginate, petiolate, fleshy, green, 

 glabrous ; no venation apparent. 



Stem : primary internodes undeveloped. 



Leaves simple, entire, cauline, alternate, lanceolate, acute, exsti- 

 pulate, petiolate, finely pubescent, ciliate, pinnatinerved. 



Cardamine Impatiens, L. 



Fruit a siliqua, linear, compressed dorsally, many-seeded, with 

 the seeds in one row, dehiscing elastically with some force from the 

 base upwards by two valves and scattering the seeds ; septum thin, 

 membranous. 



Seed oblong, obtuse at each end, much compressed dorsally, 

 pale yellow, smooth ; testa thin, subtransparent ; hilum basal, 

 brown ; micropyle close to the hilum. 



Endosperm absent. 



Embryo much curved or doubled upon itself, occupying the 

 whole seed, colourless or pale yellow ; cotyledons oblong, obtuse, 

 entire, plano-convex, accumbent, very shortly petiolate ; radicle 

 slender, terete, suddenly tapered to an obtuse point which is 

 slightly curved round the apical ends of the cotyledons, equal to 

 or slightly longer than these. 



Cardamine graeca, L. 



Primary root tapering downwards, colourless, with numerous 

 lateral rootlets. 



Hypocotyl terete, rather succulent, flexuose, glabrous, purplish, 

 2'3 cm. long, 1-5 mm. thick. 



Cotyledons foliaceous, glabrous, petiolate; petiole subterete, 

 channelled above, purplish, 1-45 cm. long'; lamina rotund-oblong, 

 emarginate, dull green, rather fleshy, 1-2 cm. long, 1 cm. broad. 



Stem herbaceous. 



