TRANSACTIONS OF THE SECTIONS. 87 



8. When the virgin forest is destroyed by natural or artificial agencies, the valu- 

 able timber-yielding trees are not replaced by a young and vigorous growth of the 

 same species, but generally by a different and inferior growth, sometimes wholly 

 fruticose, occasionally only cryptogamic. 



9. Future and permanent timber-supplies must be looked for from forests yet to 

 be ai-tificially reared and systematically cultivated, consisting in great measure of in- 

 troduced or acclimatized (exotic) trees of a hardier growth than those which are 

 indigenous. 



10. There is an e\ddent and pressing want of a Board of Forests in New Zealand, 

 with a complete skilled staff suitable to the requirements of so large and so varied 

 a colony ; while a similar want exists in aU our colonies which are similarly placed. 



The author dwelt chiefly on the abuse of the bush license, on sacrifices to a blind 

 find ignorant utilitarianism that are only too common, on indiscriminate and extra- 

 vagant destruction of valuable timber arising from a loose colonial moralitj^, or a 

 tolerated evasion of the written law, and on those other errors of commission or 

 omission on the part of governments or settlers which illustrate the necessity for 

 the establishment of some authoritative form of supervision and protection over 

 the forest interests. 



He instituted comparisons between the condition of New Zealand forests and 

 the history of forest destruction and cultivation in Scotland, the Hartz Mountains, 

 and India,' pointing out the fruits of lavish waste and ignorant indifference, and 

 indicating the present forest regulations of the Hartz district in Germany * as models 

 for imitation in all our colonies. The paper concludes by showing the fertile and 

 important results likely to accrue from acclimatization-experiments in relation to 

 forest-culture in New Zealand, especially fi-om the introduction on the large scale 

 of certain of the hardier, rapidly growing trees of Tasmania and Australia. 



Is Lichen-growth detrimental to Forest and Fruit Trees f? 

 By W. Lauder Lindsay, M.D., F.R.S.E., F.L.S. 



The author's object was on the one hand to direct attention to the radical differ- 

 ences of opinion that exist regarding the eftect of Lichen-growth on trees, and on 

 the other to endeavour to reconcile those differences, and to indicate the inferences 

 that are legitimately deducible from existing data. The paper, however, was in- 

 tended to be suggestive rather than descriptive ; its aim was rather to call attention 

 to the unsatisfactory paucity and character of the facts on record, and to invite the 

 record oi facts as contradistinguished from mere opinions, than to elaborate his own 

 views or results. 



One gToup of scientific authorities regards Lichens as trtte jmrasites, and as such 

 detrimental to the healthy growth of trees, and depreciative of their value ; while 

 another group describes them as non-parasitic, as making use of trees simply as bases 

 of sup2)ort — as innocuous, or even as beneficial, to their hosts. The former opinion is 

 that unanimously held by arboriculturists and nurserymen — by all who are concerned 

 with the cultivation of timber, bark, or fruit-trees ; while the latter is that usually 

 entertained by lichenologists. 



The principal propositions of the author were the following : — 



I. That Lichens must be regarded as tnce imrasites, drawing certain at least of 

 the constituents of theirthallus from the objects on which they grow. 



In his work on ' British Lichens," published iir 1856 (p. 50), the author had 

 shown that the Lichen-thallus contains such bases as silica and alumina, iron and 

 manganese, lime, potash, soda, and magnesia, which could not have been derived 

 from the atmosphere, from which liclienologists assert Lichens derive their whole 

 nourishment. 



11. That nurserymen discard as unsaleable trees or shrubs that are Lichen- 



covered. 



* The author gave some description of these regulations after a tour through the Hartz 

 Forest in 1850 : vide Proceedings of Botanical Society of Edinburgh for 1853, and Phyto- 

 logist, vol. iv. p. 988 (1853). 



t The subject may be found treated at greater length in ' Hardwicke's Science Gossip,' 

 1867, p. 241 ; or the ' Farmer,' Oct, 9, 1867, p. 403, 



