172 ON SEEDLINGS 



Iberis pectinata, Boiss. 



Hypocotyl 10-18 mm. long. 



Cotyledons obliquely oval, very unequal at the base, obtuse, 

 somewhat truncate at the apex, or faintly emarginate, glabrous or 

 with a thin, faint line of adpressed colourless hairs along the back 

 of the petiole ; lamina in average specimens 9-10 mm. long on one 

 side of the midrib, and 8 mm. on the other, about 7 mm. wide ; 

 petiole 12-14 mm. long, channelled on the upper side. 



Stem terete, hairy, with spreading or deflexed hairs ; internodes 

 variously developed from 1-15 mm. 



Leaves cauline, hairy, with a distinct channelled midrib. 



Nos. 1-7. Linear, obtuse, tapering gradually into the petiole at 

 the base, deeply and bluntly toothed or pinnatifid. 



Isatis tinctoria, L. (fig. 174). 



Fruit laterally compressed, oblong-cuneate, broadest at the apex, 

 somewhat winged at the base and apex, woody on each side of the 

 cavity containing the seed, one- 

 celled, one-seeded, indehiscent. 



Seed cylindrical or oblong, tipped 

 with the short funicle by which it is 

 W C R W suspended from the apex of the cell ; 



FIG. m.-Isatis tinctoria. Trans- hilum and micropyle Contiguous, at 



verse section of fruit, x 8 : c, coty- the upper end of the seed, and n earest 



ledons ; B, radicle ; W, W, woody , u , ,. ,, , , 



portions of siliqua. the base of the style. 



Endosperm none, or forming an 

 extremely thin film on the inner face of the testa. 



Embryo large, filling and conforming to the seed, curved or 

 bent upon itself, yellowish ; cotyledons oblong, obtuse, entire ; 

 radicle spindle-shaped, narrowed to an obtuse point, lying along the 

 back of the (incumbent) cotyledons and slightly longer by reason 

 of its forming the curve at the apex of the seed while the cotyle- 

 dons are straight. 



Ochthodium aegyptiacum, DC. (fig. 175). 



Fruit a nut-like silicula, broadly rhomboid, short, subquadran- 

 gular, laterally compressed, covered with hard tubercles on the 

 four angles and smaller ones between ; subcarinate on the back of 

 each carpel, glabrous, pale grey, two-celled, two- seeded, indehiscent 

 and remaining attached to the pedicel ; pericarp hard, crustaceous 

 and somewhat brittle. 



Seed broadly oblong, rounded at the apex, unequal at the base 

 owing to a prolongation of the radicle beyond the cotyledons, com- 



