320 OX SEEDLINGS 



longitudinally with an indistinct midrib (no other nerves discernible 

 when fresh), glabrous, light green; lamina 4-5 mm. long, 8'5- 

 4'5 mm. wide ; petiole channelled above, slender, 2*5-4 mm. long. 



Stem herbaceous, erect, terete, pale green, glabrous; primary 

 internodes undeveloped unless the seedlings are crowded when more 

 or less elongation takes place. Adventitious roots are frequently 

 emitted from the stem where in contact with the soil. 



Leaves simple, radical and cauline, opposite, exstipulate, petiolate, 

 alternately penninerved, with the nerves incurved and uniting with 

 those above them, light green and punctate on the upper surface, 

 paler beneath, glabrous or thinly hairy on the same plant ; petioles 

 glabrous, channelled above, dilated at the base and connate. 



First and second pairs variable ; in seedlings with sufficient 

 room to develop they are deltoid, obtuse, obscurely or obsoletely 

 dentate, with a prominent midrib and a few alternate incurved 

 lateral nerves ; in crowded seedlings they are oval. 



Torenia Fournieri, Lind. (fig. 561). 



Primary root normal, short, tapering, giving off short lateral 

 rootlets, annual. 



Hypocotyl soft, herbaceous, erect, terete, 1'5 cm. long. 

 Cotyledons petiolate, persistent ; limb triangular-emarginate, 

 subtruncate at the base, 4 mm. long, 6 mm. wide ; 

 petiole 2 mm. long. 



Stem erect, square with acute angles, thickened 

 at the nodes and ciliate at the angles, succulent, pale 

 green ; 1st internode 6 mm. long ; 2nd 1-2 cm. ; 3rd 

 2-6 cm. ; 4th 3 mm. 



Leaves simple, cauline, opposite, decussate, ex- 

 stipulate, petiolate, triangular, or triangular-ovate, 

 acute, acutely penninerved, with the nerves sunk on 

 FIG. 561. the upper side, and prominent beneath, pubescent 

 Torenia on b o th surfaces, gradually increasing in size from 

 Nat. size. the seedling stage of the plant to the adult ; average 

 size of leaf 2*2 cm. long, 8-10 mm. wide ; petioles 

 channelled above, convex beneath, pubescent, increasing in length 

 from seedling to middle of stem in the adult plant, then again be- 

 coming shorter ; average length about 1'5 cm. 



Veronica arvensis, L. (fig. 562). 



Ovary two-celled, many-ovuled ; ovules amphitropous on axile 

 placentas ; micropyle superior. 



Fruit a capsule, obcordate, much compressed laterally, keeled, 



