124 Transactions. — Botany. 



Although the artificially i^roducecl leaves mentioned above 

 are reversions to the seedling form,-' and therefore hereditary, 

 all the same they are in such experiments as these evoked 

 directly by the environment, and they show how xerophytes 

 may be changed into hygrophytes by excessive moisture in 

 the air. Soon after these hygrophilous conditions are re- 

 moved a plant with reversion leaves will develope ordinary 

 shoots once more. The plant of Veronica cupressoides used for 

 the experiment quoted above, although still in a fairly moist 

 atmosphere (that of a greenhouse), is producing normal 

 growth. Whether in cases such as these, where both the 

 reversion leaves and the ordinary leaves, or cladodes, are 

 hereditary, continual treatment under artificial conditions 

 would keep the plant permanently changed, or whether in a 

 moist climate such as that of Westport or Greymouth the 

 reversion form would endure under natural conditions, can 

 only be ascertained by experiment.! 



Generally speaking, the plant -life of the whole of this 

 region is scanty. It is only in certain places where shelter, 

 richer and deeper soil, or moisture favour growth that any- 

 thing like luxuriance may be seen. To the casual observer a 

 hillside in the lower mountain region would seem clad merely 

 with dry, brown tussock-grasses, but careful search will I'eveal 

 a number of lowly plants growing in the shelter that such 

 tussocks afford. The same remarks apply to the higher 

 regions, where many of the plants are small, low-growing, 

 -often moss-like, and by no means numerous on the expanse of 

 clayey or stony dry ground. Since the conditions of soil and 

 climate do not permit a luxuriant plant-covering over con- 

 siderable areas, it seems hard to understand how introduced 

 plants can have spread so abundantly. Even in 1869 Mr. 

 J. F. Armstrong recorded 178 for Canterbury, and this list 

 has been since extended in the " Students' Flora of New Zea- 

 land." Now, the land on which such especially flourish is 

 that which has been reclaimed by man, the rich drained 

 swamp lands and their environs, or even the more stony 

 ground ploughed and made suitable for plant-life. In such 

 virgin soil, inhabited formerly by plants which would not 

 require quite the same food-material, introduced plants would 

 flourish and have flourished amazingly. On ground untouched 



* Cockayne., loc. cit., p. 357. 



t Prom what is said above it seems evident that the two cases 

 {Olearia cymbifolia, and Veronica lycopodioides) mentioned by Captain 

 Hutton in " Darwinism and Lamarckism " (New York and London, 18'J'J, 

 pp. 217, 218) are both examples of one and the same plienomenon, and 

 not — the former an example of an acquired habit which had not become 

 hereditary, and the latter an example of an acquired habit which had 

 become hereditary. 



