Cockayne. — Development of Seedlings. 89 



Leaves (1 and 2) alternate, ovate-lanceolate to obovate, 

 usually tapering at base into petiole, entire for lower half, 

 serrate for upper half ; serrations regular or varying in depth 

 and size ; apex sometimes rounded, sometimes semitruncate, 

 or, again, the upper half of the leaf is not fully developed, and 

 looks as if bitten or torn across the middle, as in figs. 23 and 

 24, Plate IX. ; midrib raised on both surfaces. 



3rcl leaf : Fig. 13 shows this in state of development ; the 

 toothing is very even and conspicuous, and shape linear- 

 lanceolate, becoming quite lanceolate or obovate-lanceolate in 

 the fully developed leaf. 



Later leaves larger than the earlier ones, but still of same 

 type, though narrower in proportion to tTieir length ; in young 

 plant 8 cm. high not defiexed downwards, but the leaf-blades 

 are horizontal and point slightly upwards, 10cm. long x 4'5cm. 

 broad ; in other plants narrower than this, and sometimes 

 with upper half abortive ; midrib very strong ; veins distinct ; 

 petioles short, stout, erect, channelled above, swollen and 

 articulated to stem at base. 



Stem erect, terete, pale-coloured, rather shining, soon 

 becoming naked through shedding of leaves, and so marked 

 with leaf-scars. 



The stage between the earlier seedling forms and the 

 mature form I have not seen, but of this latter Mr. Cox has 

 sent me a most complete set of fruiting specimens, showing 

 also every form, I should take it, of mature leaf. These adult 

 leaves do not vary to any very great extent from the later 

 seedling ones as figured in figs. 11 and 15, and described 

 above from older specimens ; the main distinction is in length 

 and width, they being much narrower in proportion to their 

 length. Sometimes the leaf is almost entire, narrow lanceo- 

 late, with an acute apex ; at other times the apex is truncate, 

 and then toothed and cut in many ways ; while, again, the 

 upper third of the leaf may be undeveloped or abortive. To 

 approach the difficult question as to why the early form of 

 the Chatham Islands plant should differ so much from the 

 closely allied varieties in New Zealand, and not go through the 

 stage with tall upright stem and exceedingly long, narrow, de- 

 flexed leaves, would require a most intimate knowledge of the 

 environment of this plant in the Chatham Islands, which could 

 only be learnt by careful investigations on the spot. 



The deflexed-leaf form of New Zealand is possibly an 

 adaptation for pushing up to the light through more or less 

 dense surrounding vegetation, spreading leaves under such 

 circumstances of growth being a disadvantage. In the Ghat- 

 ham Islands the opposition from neighbouring plants may be 

 less, and so the defiexed leaves would be no advantage to the 

 plant ; but all this is the merest surmise. It is worthy of 



