410 35. SAXIFRAGACE^. 



425. Saxifraga aizoides, Linn.Ac/^.///[j^^j^ 



Area ******* [8 9] 10 11 12 13 * 15 16 17 18. 



South limit in Yorkshire and North Lancashire. 



North limit in Orkney and Sutherland. 



Estimate of provinces 8. Estimate of counties 20. 



Latitude 54 — 60. Highland type of distribution. 



A. A. regions. Midagrarian — Superarctic zones. 



Descends to the coast level, in the West Lowlands. 



Ascends to 1050 yards, in the East Highlands. 



Range of mean annual temperature 48 — 36. 



Native. Uliginal and Rupestral. Were we to judge by 

 the analogy of Saxifraga stellaris, Oxyria reniformis, and 

 other of the more frequent Arctic- agrarians, with which the 

 S. aizoides is so usually associated in the Highland pro- 

 vinces, as well as in the north of England, we should con- 

 fidently expect to find it accompanying the same species in 

 Wales; and yet it is apparently quite absent therefrom. 

 This absence seems the more remarkable, because the S. 

 aizoides is less strictly a mountain plant than the S. stel- 

 laris or Oxyria reniformis. We have a somewhat parellel 

 instance in the Alchemilla alpina. The S. aizoides is very 

 scarce in the midagrarian zone ; but I feel necessitated to 

 consider it as an inhabitant of that zone, since it was dis- 

 covered by Dr. P. W. Maclagan, on the coast rocks of Ayr- 

 shire. In Cumberland, also, it decends rather below 100 

 yards, along the streams in the mountain valleys ; growing 

 there on a level with plants which I have considered not to 

 rise above the midagrarian zone. In the north of Suther- 

 land, it occurs by road sides, veiy slightly above the sea 

 level, and not in the immediate vicinity of mountains ; for 

 instance, about Tongue. On the eastern side of Scotland, 



