220 



ON SEEDLINGS 



Endosperm in the mature seed forming a round mass between 

 the embryo and the basal notch, also an extremely thin layer round 

 the periphery of the seed, and surrounding the embryo, floury, 

 white. 



Embryo long and narrow, curved round the periphery of the 

 seed, pale yellow ; cotyledons linear, obtuse, entire, semiterete, 



FIG. 199. Cerastium arvense, x 15. 



lying hi the narrow way of the seed with their backs to the hilum ; 

 radicle cylindrical, slightly narrowed to an obtuse tip, somewhat 

 shorter than the cotyledons and incumbent. 



The form and arrangement of the seeds in Caryophylleae has 

 been already referred to (see ante, p. 25). 



Seedling (fig. 200). 



Hypocotyl erect or slightly decumbent, 

 thickened upwards, glabrous, pale green, 

 about 4-5 mm. long. 



Cotyledons ovate-lanceolate, obtuse, 

 petiolate, glabrous, slightly mucronate, 

 distinctly one-nerved, tapered at the base 

 into the petiole ; lamina about 7 mm. long, 

 and 3 mm. wide ; petiole channelled above, 

 convex beneath, perfoliate at the base, 

 about 3 mm. long. 



Stem herbaceous, primarily erect, 

 ultimately decumbent, terete, pale green, 

 glabrous, somewhat thickened at the 

 nodes ; 1st internode 4-25 mm., 2nd 6'5 

 mm. long. 



Leaves simple, entire, cauline, opposite, exstipulate, petiolate, 

 slightly hairy above and occasionally on the midrib beneath (at 



Half nat. size. 



