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never seen the primrose with obtuse sepals, however, though the cowslip has the sepals 

 acute, obtuse, or quite rounded at the apex. The experiments on which Professor 

 Henslow lays so much stress, are certainly of great value in relation to the distinctions 

 of species, not merely in the genus Primula, but for systematic Botany generally. Still, 

 they may be said to require confinnation ; and one confirmation which appears to be 

 requisite, is, that the experiment should be repeated by some botanist who would stu- 

 diously avoid letting his gardener or any other party know the object of his experi- 

 ment. I was once told by a gardener, that he had helped his master's horticultural 

 experiments, during the absence of tlie latter, so as to produce the results which he 

 supposed would gratify his master. — Heioett C. Watson; Thames Ditton, May 1, 1841. 



J 56. On the immersion of Specimens of Plants in Boiling Water, (Phytol. 189). 

 Having been induced from a report in ' The Phytologist ' to try the effect of boiling- 

 water in preserving the colours of botanical specimens, I was much disappointed to 

 find that it was, with me, quite ineff'ectual. Lathraea squamaria, one of the plants 

 mentioned in the report, turned completely black on remaining in boiling water ten 

 seconds ; and in one specimen which was but partially immersed, that part only turned 

 black, whilst the remainder has preserved its colour in a slight degree. By the same 

 treatment the colour was extracted from the flowers of Orchis mascula, leaving the 

 petals of a dirty brown hue ; whilst specimens dried by the usual method partially re- 

 tained their colour, and certainly their form, which the boiled ones did not. Speci- 

 mens of other plants which I tried were all acted upon in a similar manner. It cer- 

 tainly appears very strange to me that others should succeed so perfectly, whilst T, using 

 exactly the means prescribed, could not succeed in the least; and I think there must 

 be something more than has yet appeared, either in the water or the subsequent treat- 

 ment, in order to preserve the colour of such plants as Lathreea squamaria &c. — Joseph 

 Sidehotham ; 26, York St., Manchester, May 5, 1842. 



157. True office of the Earth in relation to Plants. As the article ' On the true of- 

 fice of the earth in relation to plants ' (Phytol. 173), seems to have been penned for the 

 purpose of exciting discussion, I am surprized that you have as yet luid no communi- 

 cations on the subject. I take the liberty of sending you a few remarks, as I cannot 

 subscribe to the opinion which, in that article, Mr. Newman has endeavoured to main- 

 tain. The feeding of plants in order that they may afford food for man, is an impor- 

 tant subject at this time; and if I understand Mr. Newman rightly, he maintains that 

 the earth or soil in which they grow has nothing to do with the supplying this food. 

 He makes this inference from the fact that hyacinths grow in water ; and to this in- 

 stance he might have added those of floating water-plants, of most of the Orchideae, 

 and a number of mosses, lichens, 'Sec, which evidently derive their nutriment from 

 sources independent of those constituents of the earth or soil in which they do not grow. 

 But this does not at all prove Mr. Newman's position, that those plants which grow in 

 the earth do not derive their sustenance from the soil in which they are placed. The 

 fact is that plants, like animals, require different kinds of food, and they are always 

 naturally placed in those positions in which they ai'e best supplied with their peculiar 

 food. All plants, it may perhaps be stated, require for their growth water and carbo- 

 nic acid, and they obtain these from the soil or the atmosphere, according to their 

 structure, which is adapted to the peculiar localities in which they live. The plants 

 of the deep sea, and most of the lower forms of Cryptogamia, obtain these agents by 

 their whole surface ; but in the higher forms of Phanerogamous vegetation, the func- 

 tion of absorption is exceedingly localized, and these plants seem to be almost cou- 



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