388 LEAF-ANATOMY OF THE GENUS ANDROPOGON, 



7. The stomata are present on both the inferior and superior 

 surfaces, and in about the same proportion, approximate!}^ 3:1. 

 Occasional trichomes can be seen on the inferior surface. 



Andropogon sericeus R.Br. (Plate xxix., fig. 1). 



Leaves of this grass, from two widely divergent localities, viz., 

 Nyngan and the Botanic Gardens, were examined, but no essen- 

 tial difiierences between them could be found. In the widest 

 portion of the leaf, there are five primary bundles, thirty-two 

 secondary bundles, two intermediate bundles, and ten bundles of 

 a secondary type, but which have sclerenchyma developed on the 

 inferior surface. 



As in A. affinis and A. hitertnedius, there is only one primary 

 bundle in the midrib proper. The sclerenchyma, both on the 

 superior and inferior surfaces of this bundle, is much better 

 developed than is that of A. ajfinis. The development of scler- 

 enchyma throughout the leaf, is much greater than in A. affinis, 

 but not so great as in A, ischcemu7)i. 



The epidermal cells on the inferior surface are very irregular 

 in character, and very many are papilliform. The epidermal 

 cells on the superior surface partake of the character of bulliform 

 cells except, as in A. ajfinis, above the primary bundles. 'I'hey 

 are more numerous, however, than in A. affinis, in series of 7 to 

 9, and decidedly fan-shaped in character. Trichomes and stomata 

 are numerous on the inferior surface, and a few of the latter may 

 be seen on the superior surface. Those on the inferior surface 

 are, as a rule, guarded by papilla-like cells. The cuticle is com- 

 paratively thin, and, unlike A. ischcemum, of uniform consistency 

 throughout. 



Andropogon iscHiEMUM Linn. (Plate xxxi.). 

 In a transverse section, there may be seen four types of bundles, 

 namely, primary, secondary, intermediate, and a fourth type, 

 which has sclerenchyma developed on both the superior and 

 inferior surfaces, but not in direct contact with it. In the 

 widest portion of the leaf, there are eleven primary bundles, 

 forty-six secondary bundles, twenty of an intermediate type, and 

 two of the fourth type. 



