594 REVIEWS. [October, 



shire. Through the courtesy of Mr. Sim we are indebted for 

 examples from Scone Woods which 'prove that he has reported 

 the right species ; but he explains that at the Scone station it 

 grows in proximity to a quarry into which the proprietor of cer- 

 tain extensive nursery-grounds is in the habit of pouring rubbish 

 from his gardens; and it would appear that from this quarry 

 both the Aremonia and Potentilla Mrta, of which he has also 

 forwarded a specimen (for a notice of which see the August num- 

 ber of the ' Phytologist^), have had'' their origin. Such being 

 the case, it is no doubt quite safe to infer that in the other two 

 places where the Aremonia has become established^ it has been 

 introduced under similar circumstances. 



" Cotoneaster vulgaris. Mr. Flower writes from Beaumaris, 

 'The Cotoneaster is fast disappearing from the Great Orme's 

 Head ; two or three small plants are all that are remaining, and 

 I fear that it will soon be added to the list of extinct species.' " 



Papers read to the Botanical Society of Edinburgh. By George 

 Lawson, F.R.S., S.A., P.R.P.S., F.B.S., etc. etc. 



I. Remarks on dust-showers, with notice of a shower of mud 

 which occured at Corfu on the 21st of March, 1857. 



" A singular meteorological phenomenon occiu'red here on Saturday, 

 the 21st of March. The day was squally and showery; those light 

 showers brought down a great quantity of mud; the next morning I 

 found the cauliflowers covered over with this fine dust. On examining 

 the surrounding fields I found the trees and every other object covered in 

 the same manner. As some writers have asserted, and others have de- 

 nied, that the same phenomenon is of frequent occurrence in Malta, I 

 send you a few leaves with the precipitate still upon them, which will, I 

 think, put the question to the test for ever. The second question is more 

 difficult to solve ; viz. is this native dust, or has it been imported by 

 aerial currents from Africa ? From the state of the weather during the 

 three previous days, I am led to favour the latter opinion." (Extract of 

 a letter fi'om Mr. Mackenzie, Corfu, to Dr. Lawson.) 



Dr. Lawson notices in detail similar showers of dust, which 

 had fallen at different times and in different parts of the world, 

 and quoted the opinions of learned men thereon. He found, on 



