152 



ON SEEDLINGS 



Cotyledons obovate, obtuse, slightly emarginate or nearly entire, 

 tapering into the broad petiole, which is connate at the base, alter- 

 nately and ascendingly penninerved, but venation discernible with 

 difficulty, light green above with a purple midrib, much paler be- 

 neath, glabrous, 3'5-6'2 cm. long including the petiole, 2-2*5 cm. 

 wide near the apex. 



Stem erect, herbaceous, annual, developing when about to flower ; 

 primary internodes undeveloped. 



Leaves radical and cauline, alternate (first pair opposite), nerves 

 alternately incurving, strongly reticulate, and giving off short more 

 slender branches into the marginal lobes or teeth, margin spiny, 

 subsucculent, thinly hairy on both sides with soft, whitish, jointed 

 hairs, deep green above, with a purple midrib, and marked with 

 broad grey or whitish bands ; petioles semiterete with broad shallow 

 channels above which are generally purple with green margins, 

 green beneath, thinly hairy or slightly woolly at the margins, dilated 

 at the base and semi-amplexicaul or those of the first pair connate. 



Nos. 1 and 2. Ellip- 

 tic, obtuse, margin un- 

 equally spiny-toothed. 



Nos. 3-6. Elliptic or 

 oblong-elliptic, very ob- 

 tuse, lobulate and spiny- 

 toothed. 



Silybum Mariana m, 

 Gartn. (fig. 481). 



Primary root long, 

 tapering, fleshy, colourless, 

 giving off lateral fibres, 

 biennial. 



Hypocotyl subterra- 

 nean, stout and scarcely 

 distinguishable from the 

 root. 



Cotyledons large, foli- 

 aceous, obovate - oblong, 

 obtuse, tapering into the 

 broad, flattened petiole, 

 penninerved, nerves alter- 

 nate ; petiole about 1-7 cm. 

 long, connate and amplexicaul ; lamina 2-6 cm. long, 1-8 cm. wide. 

 Stem developed in the second year. 



FIG. 481. Silybum Marianum. 

 Half nat. size. 



