56 



XOTES OX DIPTEROCAEPS. 



Deyobalaxops. 

 The great disparity between the two cotyledons of Dryobala- 

 nops aromatica has been known for over a century; a tree of 

 such economic importance naturally attracted the ' attention of 

 early voyagers in the Malay region, and Gaertner about a 

 century and a quarter ago was able to examine its seeds, and to 

 figure them in his Be fructibus, 1788-91. Then again Correa de 

 Serra in the Memoires du Museum d'Histoire Naturelle, i. 1815. 

 p. 159 and Colebrooke in the Asiatich Researches, iii, 1816. figur- 

 ed it; later others. But apparently the actual germination has not 

 been described, though the dehiscence of the fruit has been re- 

 corded as along three defined lines, and abundantly commented on. 



Figure 38 is of the young seedling seen from the side, and 

 figure 39 of its cotyledons seen from above. The larger of these 

 cotyledons is slightly cup-shaped when expanded, the other slightly 

 humped : and they come to stand horizontally. Their upper surface 

 is as rough as that of a Bipterocarpus, but their cells are full of 

 chlorophyll. 



Figures 38 and 39, the seedling of Dryobalanops aromatica from the side 

 and from above, showing how the cotyledons expand, how unequal they are, 

 and how uneven is their surface ; nat size. 



Figure 40 is a section down the germinating fruit showing 

 the radicle extruding and curving earthwards. It shows also the 

 extraordinary invagination of the placenta,, of which the genesis is 

 unstudied, and the function if any, quite obscure. This invagina- 

 tion is like an apron in shape ; round its edges at either side curves 

 the dorsal cotyledon embracing with it the inner or placentar coty- 

 ledon. 



Jour. Straits Branch 



