SO?J Dr. G. Dickie on the Altitudinal Range 



someter) was guessed as being not under 1400 feet, and upwards 

 of fifty miles inland from Aberdeen. 



Grimmia spiralis. Has not been seen in this county lower 

 than 2200 feet ; the upper limit is unknown to me. 



G. torta appears on cliffs in the vicinity of Ballater at 1400 

 feet ; I have observed it in Glen Callater at 2300 feet, but cannot 

 state its absolute highest limit. 



G. ovata appears on the hill of Fare at 600 feet ; 1 have also 

 seen it on the top of Noath at 1830 feet ; it grows on the inside 

 of the wall of the vitrified fort. In general outline this ruin is 

 elliptical; the walls are vitrified on the inside, and inclose a smooth 

 grassy sm'face at the very summit of the hill. The wall is de- 

 ficient at the east side ; the species in question is mostly confined 

 to the inside of the wall at the west end, and consequently oppo- 

 site the opening alluded to. Are we to conclude that the seeds 

 of the plant had been conveyed by the wind from some distant 

 locality ? for I did not see it on any other part of the hill. 



Tor tula tortuosa occurs on serpentine, near Ballater, at 1800 

 feet of elevation. 



POLYTRICHUM. 



All the British species grow in this county. 



In the immediate vicinity of Aberdeen the following species 

 are found : Polytrichum undulatum, hercynicum, piliferum, juni- 

 perinurUf commune, urnigerum, aloides, nanum ; of these P. hercy- 

 nicum is rarest ; I have seen it sparingly four miles inland on very 

 old walls along with Bartramia ithyphylla, Mr. Mackay found 

 it more abundant seven miles west from Aberdeen, and it grows 

 in considerable quantity about the base of the hill of Fare. In 

 the same vicinity, but at an elevation of 900 feet, Polytrichum al- 

 pinum grows in considerable quantity. P. septentrionale is con- 

 fined to our higher summits ; it is abundant about the top of 

 Ben-na-Muich-Dhu. Mr. Mackay informed me that he had 

 found it very sparingly on the top of Lochnagar. 



Lowest. Highest. 



Polytrichum hercynicum ... 50 feet. 3000 feet (highest ?) 



piliferum 50 1800 „ 



■ — juniperinum ... 50 1700 „ 



septentrionale... 3800 4000 and upwards. 



alpinum 900 3800 



Entosthodon Templetoni. Has been found in small quantity 

 by Mr. Mackay near Ballater, forty-two miles inland, at about 

 800 feet. 



Orthotrichum Hutchinsice. Is rare in Aberdeenshire ; I have 

 seen it very sparingly in Glen Callater, not lower than 2000 feet, 

 but cannot state how much higher it attains. 



Bryum julaceum. Grows in considerable quantity a few miles 



