170 Analysis of Scientific Books and Memoirs. 



placed a drop of the water, mixed with the hrownish-red colouring mat- 

 ter, under the microscope, when it was immediately seen to consist of a 

 number of round globules, sessile, of a blood-red colour, shining but 

 opaque, perfectly agreeing with Mr Bauer's figure. Some, however, of 

 the elobules were not coloured, but clear as water and transparent. The 

 size of ours was somewhat different from that stated by Bauer, 155 of a 

 line, and some of the globules were scarcely half so large as others. In 

 general, if we may be allowed to make a relative comparison, their dia- 

 meter was ten times greater than those of Tremella omenta. The mode 

 in which these globules were clustered was very irregular ; sometimes 

 they were seen single, sometimes two or three in a line, at other times in 

 irregular groupes, especially when the sediment is shaken up and the glo- 

 bules mingled together. 



Lepraria kermesina is a plant which Baron Wrangel had found in the 

 province of Nerike, Eometimes resembling a thin crust or scurf on white 

 limestone ; sometimes dissolved with the rain-water upon these same 

 stones, of a blood-red colour, and leaving a faint smell of violets, which 

 gave occasion to Baron Wrangel to imagine his plant to be the Byssus 

 jolithus of many authors. This is the same plant of which Linnaeus speaks 

 in his Journey to Westgotha. By accurately observing this plant with 

 the microscope, I not only found my supposition respecting the near re- 

 lationship of it with Uredo nivalis to be confirmed, but I fully satisfied 

 myself that both belonged to one and the same species. From this, it 

 appeared to me clear, that, as the Lepraria kermesina Aid not fall with the 

 rain, it was as little likely to be the case with the Red Snow. 



Although it has not been clearly proved, yet, as I have shown in ano- 

 ther place,* it is very probable, that, in the production of the lower orders 

 of Algce, as of the Animalia infusoria, (which come so near the one to the 

 other,) they sometimes not only pass into each other, but that they are 

 different states of one and the same thing. Next to warmth, light has the 

 most important effect in their formation. Further we know, that when 

 plants of a higher formation grow on white limestone it induces a red co- 

 lour in the flowers. It will, therefore, have a similar, or more decided, 

 action on those plants, such as the Algw, where colour is more essential. 

 We find, for example, the Anthyllis vulneraria, var. coccinea, only on chal- 

 ky ground ; so, also, among the Algw the Tremella cruenta,f E. Bot, the 

 red coloured Byssus cobaltiginea and the Lepraria kermesina occur only 

 on limestone or calcareous ground. That the light here produces the red 

 colour is proved in the Lepraria kermesina, for the colour, in such places 

 where the light was weakest, (as in the crevices of the limestone, where it 

 could scarcely gain admittance, or on the under-side of stones,) passed from 



* See the author's very curious work on the Metamorphosis of Plants, published 



at Lund. 



t Tremella cruenta is most assuredly, in this country, found in situations far re- 

 moved from limestone, or any thing approaching to a white colour, upon damp 

 black rocks in shady places, and dark brick walls in the shadiest parts of large 

 towns and cities.— H. 



