234 ON SEEDLINGS 



the apex. The same type of cotyledon is seen in Gentiana 

 verna (fig. 525), but the lamina is cuneate at the base and 

 tapers into the petiole, which unites with its fellow and forms a 

 little cup round the axis. The first five pairs of leaves are 

 precisely like the cotyledons except in being slightly larger. 

 In each case a midrib is the only apparent venation. The 

 cotyledons of Swertia corymbosa are small, triangular-ovate 

 and subtruncate at the base. Those of Erythrjea pulchella 

 are oblong-ovate and very small. 



The seedling of Orphium frutescens (fig. 524) is remark- 

 ably distinct from any of the above. The cotyledons are 

 shortly linear, without any apparent venation. The first five 

 pairs of leaves are linear- spathulate and one-nerved, increasing 

 in size from the first onwards. The primary internodes of the 

 stem, which ultimately becomes shrubby, are elongated. 



Exacum bicolor, Eoxb. (fig. 523). 



Hypocotyl erect, terete, glabrous, pale green, 1-3 mm. above the 

 soil. 



Cotyledons rotund-ovate, obtuse, petiolate, glabrous ; lamina 

 3 mm. long, 3 mm. wide at the base ; petiole channelled above, 



1-5 mm. long. 



Stem herbaceous, elon- 

 gated when about to flower, 

 glabrous, two - edged, pale 

 green ; 1st internode unde- 

 veloped; 2nd and 3rd each 

 about 1'5 mm. long. 



Leaves simple, entire, 

 radical and cauline, opposite, 

 exstipulate, petiolate, gla- 



FIG. 523. Exacum bicolor. Nat. size. brOUS, shining On both SUT- 



faces, deep green above, paler 

 beneath ; petioles convex on the back, channelled on the upper side. 



First pair small, lanceolate-elliptic, obtuse, trinerved at the 

 base, tapering into the petiole. 



Second and third pairs elliptic, obtuse, trinerved, tapering into 

 the petiole. 



Exacum macranthum, Arn. 



Hypocotyl colourless, 2-3 mm. long, with a slight ridge. 



Cotyledons very similar to those of E. bicolor. 



