28 82. LEMNACE^. 



Agrarian region. Inferagi-arian — Midagi'arian zones. 



Descends to the coast level, in the Peninsula. 



Ascends to 100 or 200 yards, in England. 



Range of mean annual temj)erature 51 — 47. 



Native. Lacustral. Said to occur at Lochend and 

 Duddingston Loch, Edinburgh, which appears to he the 

 only place where it is known in Scotland ; if, indeed, it 

 does truly grow there. It is rej)orted to be found near 

 Livei'pool, Warrington, Manchester, York, Beverley, and 

 Grimsby. Are there not other localities, to the north- 

 ward of the line that woiJd be traced across England by 

 connecting these six towns ? 



1140. Lemna polyrhiza, Linn. 



Ai-ea 1 2 3 4 5 6 7 8 9 10 * * * 14. 



South limit in Devon, Isle of Wight, Kent. 



North limit in Edinbm-gh ; — or York, Lancaster. 



Estimate of provinces 12. Estimate of counties 50. 



Latitude 50 — 56. English type of distribution. 



Agrarian region. Inferagrarian — Midagrarian zones. 



Descends to the coast level, in the Peninsula. 



Ascends to 100 or 200 yards, in England. 



Range of mean annual temperature 51 — 47. 



Native. Lacustral. Almost the same apparent limit 

 northward may be traced for this species, as for the pre- 

 ceding, with the single outhdng locality of Edinburgh. 

 It is, however, more frequentlj"- included in local lists of 

 English plants, and would seem to occur more commonlj^ 

 than the L. gibba. At the same time, it should be re- 

 membered, that the latter is more likely to be overlooked, 

 on account of its closer resemblance to L. minor. Pro- 

 bably enough, L. polyrhiza will yet be found in other 



