TT 107 - 



a comparatively early stage, one of them ceases to grow. It 

 persists for a eonsiderable time, and apparently does not 

 attain a greaterlength than about 3"". The other continues 

 to develop, and maj reach the length of 14™"°, this being the 

 measurement of the largest under observation. The smaller 

 is ovate-elliptical short-stalked; the larger usually approxi- 

 mates to the leaf in form, the stalk being as long as the blade. 



Enlargement of one of the cotjledons, as is well known, 

 occurs in other Gesneraceae. In some species of Streptocar- 

 pus^ one of the cotjledons ceases to grow, while the other 

 persists, increases greatly in size, and becomes the only foliar 

 organ of the plant. In other species (1), one c ityledon 

 becomes leaf-like, buc is succeeded by true foliage leaves. 



Both cotyledons oi Saintpaulia areprovided withapicil 

 water-stomata situated abovethe ends of the veins. Usually 

 there is only one (figs. 14, 15, 16, w), but two, lying close 

 together(fig. 14, i^'),are of common occurrence. Bifurcation 

 of the veins takes place occasionally (fig. 14, v'), the branches 

 leading either to a single water-stoma, or to a pair. 



Minute capitate glandular hairs (fig. 15, g) are found on 

 the underside, and club-shaped ones (figs. 14, 16, m) on 

 the margin, of the cotyledons, at an early age. Long, taper- 

 ing, non-glandular hairs soon appear. These, grown much 

 longer, and the capitate glandular ones still minute, occur 

 on the adult leaves. 



St-Andrews,Feb., 1898. 



(1) Cf Dickson, On the Germination of Strcptocarpus cauïescefis. 

 Trans. Bot. Soc. Edin'-., vol. XIV, p. 362. 



