146 ON SEEDLINGS 



Stem herbaceous, annual, terete, erect, more or less glandular- 

 hairy and densely stellato-tomentose ; 1st internode 3-4-5 mm. 

 long ; 2nd undeveloped ; 3rd 1-5-2 mm. long. 



Leaves narrower than in M. incana. 



Nos. 1 and 2. Opposite, oblong, obtuse, entire. 



No. 3. Linear-oblong, obtuse, entire or with one or two very 

 short obtuse teeth. 



Nos. 4-6. Linear, obtuse, with one or two blunt deltoid or sub- 

 triangular teeth on each side. 



Nasturtium sylvestre, E. Br. 



Primary root tapering downwards, provided with lateral rootlets. 

 Hypocotyl short, erect, hardly appearing above the surface of 

 the soil, obconical. 



PIG. 158. Cheiranthus Cheiri. 



1, Transverse section through middle of seed, x 11. 



2, Vertical section of seed, x 11 : M, micropyle ; F, funiculus ; Ch, chalaza. 



Cotyledons subrotund or oblong, obtuse, emarginate, subfleshyj 

 glabrous, green, indistinctly one- Veined, petiolate ; petiole rather 

 long, channelled on the upper side. 



Stem with primary internodes undeveloped. 



First leaves simple, coarsely crenate, radical, alternate, oblong, 

 obtuse, petiolate, exstipulate, hairy, especially on the upper side, 

 green, distinctly pinnatinerved ; petioles rather long, deeply chan- 

 nelled on the upper surface. 



Cheirauthus Cheiri, L. (fig. 158). 



Fruit a siliqua, linear, compressed dorsally, two-edged or sub^ 

 tetragonal, two-celled, dehiscing by two valves from base to apex ; 

 placentas many-seeded, parietal ; septum thin, membranous, formed 

 by extension of the placentas. 



Seed oblong-oval, much compressed laterally, with the edges 

 produced all round into a thin membranous wing ; seed- coat 



