BIGNONIACEyE 337 



are rotund and five- to seven-angled with a strong nerve 

 running into each angle or tooth. The ultimate leaves 

 are bipinnatisect. 



Crescentia Cujete (fig. 575) represents a third type having 

 broadly oblong-ovate, emarginate, three- or faintly five-nerved 

 cotyledons. The first pair of leaves are elliptic, and the 

 ultimate ones are greatly elongated and vary from linear- 

 lanceolate to elliptic-lanceolate. 



The cotyledons of Pithecoctenium muricatum (fig. 570) 

 are triangular, slightly emarginate, and obsoletely trifid. The 

 first two pairs of leaves are pinnately trifoliolate with elliptic 

 leaflets. 



A fifth type is met with in Incarvillea Olgae (fig. 573) 

 which has triangular, emarginate cotyledons, truncate at the 

 base and faintly multinerved or striated. The two first pairs 

 of leaves are ovate with a few serratures about the middle. 

 I. compacta differs in having reniform, trinerved, broadly 

 and shallowly emarginate cotyledons. The first leaf is oblong, 

 slightly emarginate, cordate at the base, but otherwise entire 

 and unsymmetrical. 



The sixth type occurs in Bignonia insignis (fig. 569) and 

 is the only instance of the kind observed. The cotyledons 

 are thick, fleshy, and amalgamated in one piece, and remain 

 in the seed after germination, keeping fresh for many weeks 

 even if they fail to germinate. The first pair of leaves 

 are small and scale-like ; the second, third and fourth pairs 

 are cordate, foliaceous and simple ; while the fifth pair 

 have each a pair of leaflets and a terminal tripartite hooked 

 tendril. 



Bignonia insignis, Hort. (fig. 5G9).. 



Sypocotyl undeveloped or short and subterranean. 



Cotyledons oblate, more or less emarginate, deeply subter- 

 ranean and remaining in the oblate winged seeds until these 

 decay, shortly petiolate, with the petioles unequally developed to 

 accommodate the exit of the plumule. 



Stem in the early stages erect, terete, finely and minutely 

 pubescent, pale, dull or brownish-green, sometimes rosy red, ultim- 

 ately woody and climbing ; 1st internode 2-2'4 cm. long ; 2nd 

 8-14 mm. 



n. z 



