Miscellaneous. 237 



mists, I cannot refer the first attack to anything but atmospheric 

 influences and disturbances, causing an unlicalthy state of the vines, 

 thus rendering them a fit prey to this fungus (the germs of which 

 are floating in the air), and unable to resist its insidious attacks. 



" It would require that I should write a volume rather than a 

 letter, were I to attempt to give a complete history of my ex})criments. 

 I see in my brother's present letter a confirmation of iny own ex- 

 perience as to the new shoots and flower-buds absolutely bursting 

 forth covered with filaments of the Oidium." 



The following papers were read : — 



1. "Notes on the Flora of Dumfries," by W. Lauder Lind- 

 say, M.D. 



The author's remarks applied to the district immediately around 

 Dumfries, radiating to a varying distance of five to ten miles from 

 the centre. 



His object was not so much to mention the floral treasures of the 

 county, as to call attention to the fact of the extreme luxuriance of 

 the common vegetation, not having noticed in any other part of this 

 country, or in any other countries, our common wild plants growing 

 to such a height or in such profusion. 



2. " Notice of Plants in the neighbourhood of Oban, and in part 

 of the Island of Mull," by David Philip Maclagan, Esq. The author 

 having resided at Oban during the months of August and September 

 last, had spent part of his time in examining the botany of the 

 neighbourhood, and now laid before the Society a notice of some of 

 his excursions, and a list of all the plants observed, amounting to 

 about 400 species. 



3. " On Plants found in Strachur, Argyleshire, and in Roxburgh- 

 shire," by W. Nichol, Esq. 



4. "On Lichens collected on the Breadalbane Mountains and 

 Woods," by Hugh Macmillan, Esq. 



5. "On Harmonious Colouring in Plants," by Professor M'Cosh. 



MISCELLANEOUS. 



On the Movements and Reproduction of the Naviculse. 

 By M. FocKE. 



The author, like Ehrenberg, refers the Biatomacece to the animal 

 kingdom, xiccording to his account the movements of the Navicidce 

 are effected by means of a kind of temporary, exsertile and retractile, 

 foot, which passes through openings discovered by the author on the 

 sides of the carapace. 



According to M. Focke, the reproduction of some species of 

 Naviculce presents a strange complication of the phtenoniena of 

 " alternation of generations " and conjugation ; Navicida bifrons, for 

 example, forms by the spontaneous division of its internal substance, 

 spherical bodies which like gemmules give rise to Surirella microcora. 

 These by conjugation produce N. sphndida, which gives rise to 



