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clipping. The shrubby bases so frequently seen of Pennantia corymbosa 

 Forst., Hoheria angustijoUa Raoul, &c, above which the flowering and 

 quite different adult rises, are not very long-lived, but finally die and 

 are cast off. In some cases the distinction between juvenile and adult is 

 equally great, as in the above, but the stability of each form is weaker, and 

 the power of the cell derived through heredity to produce one or the other 

 is present in every shoot, no matter how far from the base, reminding one 



somewhat of the behaviour of 

 a " graft hybrid." Examples are : 

 Dracophyllum arboreum Cockayne, 

 whipcord veronicas, Podocarpus 

 dacrydioides A. Rich, Aristotelia 

 fruticosa Hook. f. In Elaeocarpus 

 H ookerianus Raoul reversion 

 shoots occur high up the tree, 

 but I have not noted them in 

 the uppermost branches. In these 

 last-cited examples an observable 

 stimulus does not seem necessary 

 to bring forth the special form ; 

 it is rather as if very little indeed 

 — probably some slight internal 

 change — can suffice to upset the 

 equilibrium of the cell upon which 

 one or the other form depends. 

 An analogous example is a varie- 

 gated form of Veronica salicijolia 

 which originated spontaneously in 

 the garden of the late Mr. W. 

 Gray, of Governor's Bay, for many 

 years an enthusiastic cultivator of 

 New Zealand plants. The first 

 leaves of each shoot have an irregu- 

 lar band of green down the centre 

 of every leaf, but as these become 

 older chlorophyll gradually invades 

 the pale portion until the leaf becomes normally green. Shade leaves are 

 at first without any chlorophyll. 



Fig. 3. 



Leaf-forms of Elaeocakpus 

 hookerianus. 



a, 



small adult leaf ; b, transition to adult ; 

 c and d, early long narrow form ; e, /, 

 and ij, early obovate short form. The 

 long narrow and short obovate or rotund 

 leaves are associated with divaricating 

 branching. Life size. 



VI. Hybridization. 



Hardly anything is known as to the occurrence of wild hybrids in New 

 Zealand. But field observations on this head are, in any case, merely 

 suggestive, and, at most, pave the way for experiment. 



Long ago hybrids were raised in cultivation by Mr. Anderson Henry 

 and others in Great Britain from some of the large-leaved lowland species 

 of Veronica. What I take to be hybrids — one especially from V. pime- 

 leoides Hook. f. — have originated spontaneously in the semi- wild collection 

 of indigenous plants in the Christchurch Domain. Mr. D. L. Poppelwell has 

 sent me a hybrid from his garden which he considers V . salicijolia x V. de- 

 cumbens. It is somewhat of the salicijolia type, but with small glossy leaves ; 

 I have not seen the flowers. Recently Mr. A. Lindsay, of Edinburgh, 

 has raised one or two hybrids of which the parents are known. The 



