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i* sometimes the case, it is probable that these smaller vesicles are proliferous, 

 like the caespitose Agarics, and these minute tufts appear to wither without any 

 collapse, remaining unchanged and barren. The vesicle seems only to contain 

 air and a slight liquidity, though sometimes minute threads are observable, 

 but the sides of the vesicles contain a crowd of cells or chlorophyl globules, 

 which in maturity are closely agglomerated together, and have been called 

 "gonidia," by Itsigsohn, probably analagous to gemmae, by which the plant is 

 perpetuated. No other fructification is apparent. The cells part with the 

 minute granules or gemmae they contain, which are deposited in the mud, and 

 there rest to await a favourable time for renewing the plant in crowded in- 

 flated globules as before. The ulvoid state of the plant shows at last only 

 empty cells, and after a few days existence it withers and disappears. 



The Botrydium, in its first vesicular state, is very evanescent, for 

 unless the mud on which it grows is kept moist, it altogether dries up in 

 three or four days, leaving only a whitish inconspicuous efflorescence, and it is 

 consequently very difficult to preserve specimens except between glass. It 

 is most curious that the vesicles, which are at first separate, unite after collapsing, 

 and then form a green crust or frond of indefinite extent, which when exa- 

 mined under the microscope is found to consist of round cells or gonidia, closely 

 approximate at first, containing gemmae or granules, by which the little plant 

 is propagated ; but it is difficult to observe the escape of these granules, 

 though the cells at last are found empty. 



In hot seasons, several kinds of brilliant-coloured A Igce appear either on 

 the surface of stagnant water, colouring the water itself that is reduced to 

 puddles, or staining the mud, stones, and slabs lying in the water. A remarkable 

 appearance of this kind came under my view in the bed of the river Manifold 

 in Staffordshire, a few weeks ago. I should remark that in hot summers the bed 

 of the river Manifold becomes dry for an extent of more than four miles, and 

 the bed of the river consists of mountain limestone worn by the stream into 

 strange serratures and inequalities, with here and there a barrier of rock across 

 the course of the stream, forming in winter rapids and cascades with great 

 boulders at intervals blocking up the way. A walk up this exposed bed is one 

 of the most remarkable traverses that a naturalist can make, and it is not to be 

 accomplished without some difficulty. In several places, faking advantage 

 of the cessation of the watery flow, a mass of the Petasites vulgaris, with its 

 long-stalked gigantic leaves, chokes up the rocky bed of the river, through 

 which the wanderer must wade breast high and push on with considerable 

 trouble. 



At intervals I observed the rocks and boulders in the bed of the stream to 

 be coloured red on their surface, and where little spreads of water remained 

 they were crimsoned as if with diluted blood ; so that if any person had 

 been missed and supposed to be murdered, a detective policeman might well 

 have believed that here undoubted traces appealed of the course taken by 



