32 



that M. Cli. Martins, who twice accompanied the French expedition to Spitzhergen, 

 is of opinion that the colouring matter of red snow, Protococcus nivalis, and of green 

 snow, Frot. viridis, " are one and the same plant, only in different stages of develop- 

 ment." Prof. Meyen, however, considers it to be still a question whether the colours 

 of the snow are really produced by different states of the same species, but he has no 

 doubt that the so-called Protococci belong, not to the vegetable but to the animal 

 Mngdom, being true Infusoria; that Protococcus viridis is identical with Ehrenberg's 

 Euglena viridis and Prot. nivalis with his £Jug. sanguinea, (the Enchelis sanguinea and 

 Pulvisculus of authors) ; that these Euchelides " exhibit at times a perfectly motion- 

 less state, in which they appear spherical," and that in this state they have been de- 

 scribed as Protococci ; that " it is these spherical, reposing animalcules which often 

 appear in almost incredible numbers, and, surrounded with a kind of slime, form more 

 or less thick skins, which frequently cover the bottoms of shallow standing waters;" 

 and it is in consequence of observing that these animalcules, after long remaining in 

 this passive and inert state, occasionally resume their activity, that so many philoso- 

 phers have spoken of a metamorphosis of Infusoria into plants, and vice versa. — Ed. 



Art. X. — Proceedings of Societies. 



LINNEAN SOCIETV. 

 After the recess we intend to give full reports of the botanical papers read at this Society. 



BOTANICAL SOCIETY OF EDINBURGH. 

 The future meetings of this Society will be regularly repoi-ted : the omission in the present instance was 

 not accidental, but unavoidable, 



BOTANICAL SOCIETY OF LONDON. 

 June 4. — John Eeynolds, Esq., Treasurer, in the Chair. Dr. Killikelly (of Indiana) presented a specimen 

 of TiUandsia tJsneoides fi-om the banks of the Mississippi. 



Dr. John Lhotsky read a paper " On the Periodical Decortication of the genus Eucalyptus in Australia." 

 After describing the appearance of the bark hanging in strips from the trunks and branches of the Eucalypti, 

 Dr. Lhotsky observed that in addition to this singular effect, the varying colour of the denuded ti-unks and 

 branches, from pui-e white through all shades to deep red, presents an equally original and characteristic as- 

 pect. Little is yet known as to the period of decortication; and the questions to be determined by future ob- 

 servers are, 1 st, Whether the decortication of the different species of Eucalypti takes place at any certain season 

 or is dependent on other cu'cumstances ; and 2dly, Whether all the species decorticate at the same period, or 

 the different species at different times. The cause of a phenomenon apparent in so gi'eat a number of a 

 genus scattered most widely over the Ausfci'alian continent, is matter of importance for physical Geogi-aphy, 

 and for Botany especially. And Dr. Lhotsky thinks a clew towards its explanation may be obtained thi-ough 

 that botanical axiom, that the concentric layers of wood and bark are the reverse of each other, the foi-mer in- 

 creasing externally, the other internally. As exogenous plants (like the Eucalypti) increase by annual addi- 

 tions of new matter on their outsides, it is plausible to say, that as the growth of the Eucalypti, in almost all 

 the species, is very rapid, the alburnum of these trees extends so rapidly that the liber first becomes considerably 

 distended, then cracks, and finally separates from the trunk. The New Hollanders have largely taken advantage 

 of this phenomenon. The huts or sheds temporarily occupied by them are made of the sheets of the bark of the 

 Eucalypti. It is on such sheets that they repose, and protect themselves from the humidity of the soil. From 

 such sheets also they make their most rude canoes, (with which, however, they only navigate the lakes) ; they 

 bind them in an adequate manner, and fill up the crevices with soil and melted gum. The New Hollander 

 possesses neither flint nor steel; and as he finds it difficult to produce fire, he carries with him on his aquatic 

 excursions, a piece of a large ignited branch of an Eucalyptus, which, fi'om its resinous natiu'e, burns like a 

 torch. In conclusion. Dr. L. obsei-ved, — " Taking all this, and what I have said in previous papers, together, 

 the New Hollander may, with some degiee of propriety, be called the ' Eucalyptus-man.'— G. E. D. 



