164 



NOTES ON DIPTEKOCAEPS. 



Fig. 8. The cotyledon 

 of Shorea leprosula from 

 above, x 1\, 



At the stage reached in figure 7 the first pair of leaves are 

 ready to expand : and at this stage the heliotropism exhibited by 

 the young plant is considerable. The plant figured had been 

 illuminated from one side only. 



It will be noticed in figure 7 that one cotyledon is raised by 

 its petiole to a position slightly higher than that of the other; that 

 one is the outer : and the different angle which it tends to take, 

 mav be connected with its greater bulk and less ability to flatten 

 itself, 

 other Shoreas 



The outer cotyledon stands higher than the inner also in 



Figure 9 is of 8. rigida, Branclis, with the outer cotyledon to 

 the left. Figs. 10 and 11 are of 8. macroptera, Dyer, with the 

 same orientation. Figure 12 is of 8. bracteolata, Dyer, with the 

 outer cotyledon on the opposite side. In all the outer cotyledon 

 has taken up a position above the inner. 



Fig. 9. Cotyledons of Shorea rigida. Fig. 10. Cotyledons of Shorea 

 macroptera from above and from the side. 



This outer cotyledon is least bulky in 8. bracteolata, and most 

 bulky in 8. macroptera. The drawings indicate differences in 

 shape : but until many more Shoreas have been examined in the 

 seedling "state, it is useless to endeavour to establish relationships 

 between their shape and the sections of the genus. 



Jour. Straits Branch 



