1 86 ANNALS OF SCOTTISH NATURAL HISTORY 



the genus Porphyrops occurring in the bed of the river Nairn was 

 remarkable this was true both in individuals and species 

 P. riva/is, Lw. (only recorded from a single c? taken at Aviemore 

 last year), P. fa tula, Radd., P. n'paria, Mg., P. crassipes, Mg., and 

 another species possibly P. gravipes, Walk. occurring in great 

 numbers. 



Tabanus luridus, Fin., appears to be the common Horsefly 

 of the spring and early summer, and was met with on the sand-hills 

 near Nairn in great numbers; by good luck 4 6*'s were obtained 

 sitting on a sandy road. J. VV. YERBURY, London. 



BOTANICAL NOTES AND NEWS. 



Trees of Scotland. I shall be glad of observations and 

 measurements of trees in Scotland, also of notes on the highest 

 latitude and altitude on mountains reached by them, and their 

 habit (trees or shrubs) at these limits, more especially as regards the 

 following : 



Pyrus Aucuparia, Rowan or Mountain Ash. 



Alnus glutinosa, Alder. 



Fraxinus excelsior, Common Ash. 



Ulmus montana, Scotch or Wych Elm. 



Betula pubescens, Common Birch ") Do these occur, in the wild 



B. verrucosa, White Birch j state, over separate areas 



or mixed? Do they show any separation of different habits 

 (pendulous and upright) ? and are the habits constant for 

 the two species ? 



Qtiercus sessiliflora, Sessile-fruited Oak ) Have these distinct 



Q. pedunculala, Common Oak J areas of distribu- 



tion ? Oak is found in Orkney in peat -mosses. How far 

 north does it now occur in the wild state ? 



Salix alba, White Willow. 



S. fragilis, Crack Willow. 



Popuhts alba, White Poplar. 



P. tremula, Aspen. Does this ever occur as a large tree, i.e. 

 exceeding 60 ft. high by 4 ft. in girth ? 



Pinus sylvestris. 

 AUGUSTINE HENRY, 13 Westpark Gardens, Kew. 



Pyrus Aria in Scotland. I gather from Prof. Trail's note in 

 the current number of the "Annals" (page 123) that he would not 



