Polygonum.| POLYGONACEZ. 245 
The distribution in Ireland of this critical plant is almost 
unknown ; it will most probably be found in other localities 
in Kerry. 
P. lapathifolium Linn. 
Districts I. II. II. IV. V. VI. VIL. VIII. IX. 
Colonist. Cultivated ground and, very rarely, in waste 
places. Rather common and locally abundant bit rare 
over large areas. Ann. July—September. 
First record in 1901: R.W.S., Topog. Bot. 
While P. lapathifolium is generally much rarer in Kerry 
than P. Persicaria it is sometimes found to be the more 
abundant species over some limited area. It is very seldom 
seen outside cultivated ground, potato fields on poor peaty 
soil being its favourite habitat in the county. 
P. amphibium Linn. 
Districts — II. III. IV. V. VI. VII. VIII. Ix. 
Native. Lakes, ditches and slow streams, also on damp 
roadsides and waste places. Rather common but quite 
local or absent over large areas in the south. Peren. July— 
September. 
First record in 1901: R.W.S., Topog. Bot. 
The terrestrial form of this plant is more frequently seen 
in Kerry than the aquatic. In the neighbourhood of 
Killarney especially, the latter is a very rare plant. 
P. viviparum Linn. 
‘District Se 
Native. Damp ground ona mountain Very rare and local. 
Peren. July. 
V. On Pierasmore ridge at 2,380 feet, about a mile and an 
eighth north of the summit of Brandon, not far from the 
ruins of an old signal tower: Hart 1884. 
First record in 1884: Hart, Proc. RIA. 
This interesting alpine species appears to be limited in 
Kerry to the single station recorded above in which it is 
very rare. Elsewhere in Ireland, it occurs only on the 
Donegal and the Sligo and Leitrim mountains and revches 
on Brandon its southern limit in the British Isles. 
P. sagittatum Linn. Arrow-leaved Tear-thumb. 
District — TE -— — ~—~ —~— ~~ —- = 
Alien or Denizen. In wet boggy places and in damp or 
stony places by a stream. Very rare and local. Ann. 
July—September. 
