84. JUNCACE^. 39 



panicle of the former being usually much less effuse on 

 the northern hills, than is the case in the more southern 

 and lowland counties. Dr. Dickie, too, gives the upper 

 limit of J. conglomeratus at 700 j^'ards (London Journal 

 of Botany) ; but J. efifusus, certainly the commoner species 

 in the Highland counties, is not named in his list. The 

 true upper limit remains to be determined by future ob- 

 servation. 



1151*. JUNCUS EFFUSUS, Limi. 



Area general. 



South limit in Cornwall, Isle of Wight, Kent. 



North limit in Shetland, Orkney. 



Estimate of provinces 18. Estimate of counties 83. 



Latitude 50 — 61. British type of distribution. 



A. A. regions. Inferagrarian — Inferarctic zones. 



Descends to the coast level, in the Peninsula. 



Ascends to 800 yards, in East Highlands. 



Range of mean annual temperature 52 — 39. 



Native. Paludal, Inundatal, &c. Rises to the extreme 

 limit of the lower arctic zone, and perhaps even enters 

 slightly within the midarctic ; its upper limits m the East 

 Highland province forming a wavy Une varying from 600 

 to 800 yards above the sea ; the more frequent points of 

 cessation on the mountain acclivities being at about 700 

 yards. In North Wales, it probably attains fuU 900 yards. 

 Balfour and Babington enumerate J. conglomeratus, and 

 omit J. effusus, in their list of Hebridean plants. If 

 either of the two be really absent, I should expect to find 

 J. effusus the one growing there, and J. conglomeratus 

 the one absent. See also the remarks under the pre- 

 ceding species. 



