330 24. ROSACEvE. 



distant habitats have been recorded, in Moray ; but there 

 probably O. tuberosus was mistaken for O. niger. There 

 can be no doubt that the same error caused the introduction^ />/^ 

 of tlie latter name into Mr. Carter's list of plants seen about /./^/iT- 

 Cheadle, in Staffordshire ; and I think that the same mis- 

 take has caused O. niger to be reported from other pro- 

 vinces, also, though I have not kept notes of these errors, 

 and therefore cannot here indicate the provinces. It may 

 be as well, while alluding to an example in point, to 

 explain that the provinces within which I find species 

 erroneously recorded, or suppose them to be recorded 

 eiToneously, are indicated by their nos. in the line of 

 area, in order to put other botanists upon their guard 

 against being misled by these false habitats ; which have 

 frequently occasioned much trouble and uncertainty to 

 myself, in investigating the distribution of species. At the 

 same time, it is to be borne in recollection that the enclosed 

 iios. are not known to be errors in every instance : some of 

 them may turn out to be quite coiTCCt. 



314. Peunus spinosa, Linn. ^ y'^^.^r/i V^r. 

 314,b. Prunus insititia, JLinn. i, '. ^/i" 



314,c. Prunus domestica, Linn. 



Area 1 2 3 4 5 | 7 8 9 10 11 12 13 14 15 16 17. 

 South limit in Cornwall, Isle of Wight, Kent. 

 North limit (of P. spinosa) in Sutherland. 

 Estimate of provinces 1 8. Estimate of counties 80. 

 Latitude 50 — 59. British type of distribution. 

 Agrarian region. Inferagrarian — Superagrarian zones. 

 Descends to the coast level, in the Peninsula. 

 Ascends to 200 or 300 yards, in England. 

 Range of mean annual temperature 51 — 46. 



