256 ON SEEDLINGS 



Seedlings. There are at least five or six different types of 

 cotyledons amongst the Boraginese. One of the most remark - 

 able is that represented by Cordia latifolia which has broad 

 subrhomboid-cuneate, somewhat plaited, five-nerved coty- 

 ledons. The three primary nerves are much branched with 

 the branches terminating in the notches between the crena- 

 tures of the apical margin of the lamina. The crenatures are 

 due to the way in which the large cotyledons are longitudinally 

 folded or plaited in the seed. Other instances are met with 

 in which the midrib ends in an apical sinus, such as Brassica 

 and Convolvulus as well as all or most cases where the coty- 

 ledons are bifid or emarginate, but the case of numerous cre- 

 natures with the stronger secondary as well as the primary 

 veins ending in the notches is probably unique as far as the 

 genus Cordia is concerned. The hypocotyl of C. latifolia is very 

 short. The first leaf is small, oblong and entire, while the two 

 following leaves are much larger and thinly serrated above the 

 middle. The seedling of C. subcordata (fig. 535) is altogether 

 taller and more robust with a long hypocotyl. The cotyledons 

 are transversely oval, longitudinally plicate, and otherwise 

 like those of C. latifolia. The first leaf is ovate, acuminate, 

 and the second cordate, The cotyledons of C. decandra 

 are obovate-elliptic, plicate, crenate at the apical margin, 

 pubescent and penninerved. An exceptional case occurs in 

 C. ferruginea which has broadly obovate-cuneate, trinerved, 

 entire cotyledons. The first two leaves are oblong-lanceolate 

 and subopposite. 



A third type occurs in Lithospermum officinale (fig. 538) 

 which has obovate or roundly-elliptic, emarginate cotyledons ; 

 hairy on the upper surface. The first two leaves are opposite 

 but unequal in size, oblong-elliptic and entire. The cotyledons 

 of Echium canescens are suborbicular or oblate and hairy, 

 with a wide shallow apical sinus. 



The cotyledons of some species vary between obovate, 

 oblong-obovate and spathulate. Those of Anchusa capensis 

 are broadly obovate, entire, penninerved and hairy. The 

 first leaf is lanceolate-oblong, tapering to the base, penni- 

 nerved and hairy. Those of Echium violaceum differ chiefly 

 in having a more oval lamina. The first pair of leaves are 



