69. EUPHORBIACE^. 367 



Other circumstances than the growth of box [Buxus) there. 

 Even where the origin of the name seems perfectly clear, 

 as at Box Hill, Surrey, the shrub may have been intro- 

 duced. 



't4,/Cr/'./A' *X, ;v/ 976. Mercurialis perennis, Linn. 



t Mercurialis ovata, S. ds H. 



Area 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17. 



South limit in Cornwall, Isle of Wight, Kent. 



North limit in Ross, Aberdeen, Argyle. 



Estimate of provinces 17. Estimate of counties 75. 



Latitude 50—58. British type of distribution. 



A. A. regions. Inferagrarian — Inferarctic zones. 



Descends to the coast level, in the Peninsula. 



Ascends to 550 or 600 yards, in East Highlands. 



Range of mean annual temperature 52 — 41. 



Native. Sylvestral, Septal. A scarce plant above the 

 agrarian region ; but assigned to the lowest zone of the 

 arctic region because it was observed in the woods of Loch- 

 na-gar, Aberdeenshire, at 1720 feet, and in Twll du, Caer- 



knarvonshire, at 1750 feet. M. ovata is unknown to me. 

 From the accounts and remarks of other botanists, I sup- 

 pose it to be a slight variety of M. perennis. Mr. Mitten 

 says that it has been found in hedges, near Hurstpierpoint, 

 in Sussex. 



977. Mercurialis annua, Linn. 

 977, b. Mercurialis ambigua, L.Jil. 



Area 12 345678**11**^15. 

 South limit in Devon, Isle of Wight, Kent. 



