62 84. JUNCACEJE. 



1168. JuNcus TRiGLUMis, Linn. 



Area ******7^* (10) 11 12 * * 15 16 17 18. 



South limit iii Caernarvon, Durham. 



North limit in Shetland, Sutherland. 



Estimate of provinces 8. Estimate of counties 20. 



Latitude 53 — 61. Highland type of distribution. 



Arctic region. Inferarctic — Midarctic zones. 



Descends to 350 or 400 yards, in East Highlands. 



Ascends to 900 yards, in the same province. 



Eange of mean annual temperature 43 — 38. 



Native, Uliginal. "Whether this species should be 

 considered to descend clearly within the superagrarian 

 zone, is yet doubtful. It certainly grows at a lower ele- 

 vation than is attained by some ascending plants, which 

 in this work have not been deemed to rise above the 

 agrarian region. But as formerly mentioned (Vol. i. p. 

 41) it is difficult to draw close comparisons between the 

 lower line of one plant, and the upper line of another, 

 without making mathematical exactness interfere with the 

 natural associations of different species, in climate and 

 situation of growth. There may appear something strange, 

 in the inclosure of the Humber province (10) for J. tri- 

 glumis ; but this is done on the faith of a note by Mr. 

 Moore, in a manuscript list of Yorkshire plants, to this 

 effect ; — " originally planted on Cronkley Fell, but wild 

 on the opposite Fell." Juncus trigiumis is omitted from 

 the published Flora of Yorksliii'e. 



