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of vegetation upon the bare rocks, whose hollows they have filled up in the lapse of 

 ages with a soft spongy carpel, and so encompassed and obscured them that numerous 

 masses of grey rock, almost immersed in the verdant mossy inundation, now scarcely 

 exhibit their points above it. The lichens have been generally considered as the first 

 pioneers of vegetation, but their eff'orts to create a humus for the nourishment of other 

 plants are but trifling when compared with the economical powers of the mosses. To 

 test this by experiment, observing the tiled roof of an outbuilding at Malvern Wells, 

 evidently erected but a few years, studded with tufts of Bryum capillare, (Linn.), Mr. 

 Lees gathered one of them in March last, with the black earth collected around its 

 base. The mass altogether weighed six ounces ; bnt when, after repeated and careful 

 washings, Mr. L. had extracted all or nearly all the black mould that enveloped the 

 roots, the actual residuum of frondescence when weighed amounted to only half an 

 ounce ; thus satisfactorily showing (for no soil could have been collected on the slop- 

 ing roof, independently of the agency of the Bryum) that the moss, through atmosphe- 

 rical and imbral agency, had formed a soil exceeding its own weight at the very least 

 above ten times ! By operations on a more extensive scale, it is easily conceivable 

 how a bare mass of rock may, in the course of a few years, be covered with a thick 

 coating of soil, sufiicient for the nourishment of any of the phanerogamous species 

 adapted to the climate and elevation where they may stand. Mr. L. regretted that in 

 the experiment adduced he could not certainly determine the exact space of time that 

 the Bryum had occupied the roof ; but as it is found expedient, from the excessive 

 growth of mosses, to cleanse roofs about Malvern almost every year, Mr. L. felt cer- 

 tain that, at the utmost, the plants in question had been located on the tiles between 

 two and three years. Bryum hornum has been noticed to be a great accumulator of 

 soil in marshy spots ; while the excessive growth alone of the stems and foliage of such 

 mosses as Sphagnum palustre, Dicranum glaucum, Bryum falustre, Hypium molluseum, 

 Hypnum cuspidatum^ &c., in the course of time entirely fills up bogs, drinks up their 

 water, and conduces to their ultimate establishment as component parts of terra firma 

 fit for useful cultivation. In this manner Mr. Lees considered the Malvern Hills to 

 have received originally that rich humus which covers their sides, and which, combined 

 with the disintegrating touch of time's mouldering fingers, renders their soil, in the 

 present day, capable of immediate cultivation, even in the steepest places, producing 

 crops that well repay the toil of the industrious cultivator, and tend to give an im- 

 pulse to fresh inclosures of the verdant turf every year. On a first cursory glance 

 at the turf of the hills, there seems a great sameness in the mosses that luxuriate there. 

 Dicranum scopariuin, Hypnum triquetrum, splendens, purum and molluseum, seeming 

 as if they had united to exclude the rest, Hypnum triquetrum especially everywhere 

 predominating. However, a little attention will show a considerable variety, especially 

 upon or in the immediate vicinity of the rocks or on the margin of the numerous tink- 

 ling rills that show a cincture of the tenderest green wherever they tiickle down. In- 

 clusive of the woods about the bases of the hills, Mr. Lees had numbered 121 species, 

 without by any means exhausting the interminable Hypna, so that it is probable a few 

 more may yet be detected. Specimens of nearly all that Mr. L. had met with accom- 

 panied the paper, and many of them were exhibited. Here followed a list of those 

 observed. 



June 3. — ^J. E. Gray, Esq., F.R.S., &c.. President, in the chair. Mr. J. A. Brewer 

 exhibited living specimens of Ophrys muscifera, Aceras anthropophora, Orchis ustulata, 

 Paris quadrifolia, Mespilus germanica, and other interesting plants from Eeigate, Sur- 



