326 Queries and Answers. 



one or tlie other state in the previous embryo ? or by what power are they 

 made convertible? The subject is full of mystery; and, perhaps, as in the 

 animal, so also in the vegetable physiology, to call these the actions of a vital 

 energy we are unable to define is all the length we can yet go, and that all our 

 theories will be the better of plasticity. Perhaps, either Mr. Towers or I 

 may have extended Mr. Main's opinions farther than he thinks warranted 

 himself, and, if so, I would be glad to have a proper and correct definition of 

 them. Is the vegetable membrane the liber ? or, hke central points and axis, 

 difficult of comprehension ? — R, Lymhurn. Kilmarnock, May 13. 1840. 



Constitutional Changes in Plants hy being grown in Climates not natural to them. 

 — Did you notice what Mr. Paxton says in his last magazine (p. 80.) about 

 the corrieas which are impregnated and raised from seeds in heat ? He seems 

 to think that this treatment would affect the future hardiness of plants so 

 raised. I once saved seeds from a cucumber which ripened in the open air, 

 and thought that plants raised from these seeds would prove hardier, as a 

 matter of course. I do not think so now, neither do I think that Mr. Pax- 

 ton's opinion is right on the other side of the question ; but he is perfectly 

 right in giving a candid opinion. Nothing tends more to the advancement of 

 knowledge than that those who can think for themselves should avow their 

 opinions, and not pin their faith to the sleeves of others ; opposite opinions 

 are thus brought before the pubUc, who may canvass them till truth is sifted 

 out. I am of opinion, reasoning from analogy and from some practice, that 

 an acorn may be vegetated in a stove or melon bed, and the seedling oak 

 grown there for ten years, and if afterwards it is inured to the open air by 

 degrees, it will prove to be quite as hardy as its parent. Yea, if you could follow 

 up your seedUng oak till it produced acorns in the stove, and vegetate these 

 again in heat, keeping the seedlings in constant heat for any length of time, 

 they may be afterwards inured to the open air, and will be found just as hardy 

 as if the mother and grandmother had been raised and grown in the highest 

 latitude peculiar to the species ; and that this physiological law holds good in 

 the whole vegetable kingdom, whether hardy plants or otherwise. In thus 

 defending an opinion of mine once hastily expressed in this Magazine, I am 

 sure Mr. Paxton will not be the least offended at it. No one can appreciate 

 Mr. Paxton's useful career better than myself. — D. Beaton. May 5. 1840. 



Art. VIII. Queries and Anstvers. 



Adaptiveness of Trees and Shrubs to Soils. — Permit me to hope to see a 

 few lines from some of your correspondents on the adaptiveness of trees and 

 shrubs (both ornamental and useful) to soils ; setting forth, at one view, what 

 would best thrive on clays, on clays with a substratum of blue marl, on Shank- 

 lin sand or gait, on firestone, on light soils, on stiff* soils, &c. — E, Upper 

 Seymour Street, May 8. 1839. 



The Coccus on the Larch. — The young larch plantations here, near Melton 

 Mowbray, have been infested by the enclosed pest [a branch of larch infested 

 with Coccus laricis] during the last three summers ; and they are nov/ increased 

 to such an alarming extent that we almost despair of saving the trees. Is it 

 the Coccus laricis mentioned in the Ency. of Gard. § 6595. as seriously injuring 

 most of the plantations in Britain about the year 1805 ? [Yes.] Sickly plants 

 of the Scotch pine and the silver fir are also infested by a woolly insect, which 

 I should say is an A^phis ; however, it is evidently different from the one upon 

 the larch. To apply means for their destruction we fear would be an ope- 

 ration too formidable to encounter. I trust that you, or some of your scien- 

 tific correspondents, through the medium of your excellent Magazine, will 

 throw a little light on the subject, that we may be able to anticipate their 

 departure in the same mysterious manner as that in which they arrived ; and 

 will also inform us whether there is an instance known of larch plantations 

 having been totally destroyed by them. — F. May 6. 1840. 



