and the remainder sub-opposite. D. oppositiiolia resembles 
D. Melanoxylon in the opposite and snb-opposite arrange¬ 
ment of the leaves. In the former species, however, many 
twigs have their leaves crowded together to form large 
rosettes. 
Form and Size of Leaves . — The leaves conform to the 
usual tropical type in that they are simple, entire, and 
petiolate. The shape may be,ovate (D. ovalifolia), lanceolate 
(D. hirsute), or lanceolate oblong, with a tapering or abrupt 
apex, and a rounded or tapering base. 
The size varies considerably, being smallest (30 to 70 mm.) 
m D. oocarpa and D. pruriens, and largest (190 to 350 mm. 
long) in D. Moonii, D. insignis, and D. Embryopteris. 
Wrthm the same species there is often a considerable 
variation in size, the young leaves arising on offshoots from 
the mam stem being many times the size of those occurring 
on the normal twigs. A case in point is in the large 
leaves of D. Melanoxylon, these occurring on the young 
shoots ansins- from tha ,, . . y ® 
100 to 240 mm., whewas the „< 
species are 50 to 100 mm, 
marked degree in D. Gardneri, 
sylvatica. 
trees and measuring 
>rmal dimensions for this 
Heterophylly occurs to a 
D - oppositifolia, and D. 
=§|§=~~~ 
scattered between them. S “ aH 
project strongly on the rm J ^ vascnlar Indies 
sometimes on the lower Tnsi^ f? bryopteris >’ 
relatively inconspicuous (D. are often 
oocarpa). ’ ' ms ’ m ontana, and D. 
The midrib may be 
