J. R. Matthews. 
*38 
have very long internodes. Very few species are associated with 
Elodea, and free floating plants in any part of the loch are absent. 
Utricularia vulgaris L. has been recorded, 1 but all endeavours on 
the part of the writer to find this plant ended in failure. 2 
The following plants occur in this association :— 
Elodea canadensis d. Nitella translucens f. 
Potamogeton filiformis f. Potamogeton perfoliatus o. 
(B). Shallow water association. In the shallower water 
bordering on the reed-swamp and to some extent amongst the plants 
of this zone there is a greater abundance of aquatics. Towards the 
north side Potamogeton natans L. is dominant, with a few species 
of Nitella growing on the mud bottom. Towards the south side of 
the open water Myriophyllum spicatum L. is dominant, and with 
this plant there is a greater number of associated species occupy¬ 
ing the floor of the loch. This lower storey consists chiefly of 
Potamogeton trichoides Cham., 3 P. perfoliatus L. and Nitella 
opaca Ag. Along the east side and extending among the plants of 
the reed-swamp the bottom is carpeted with Chara aspera var. 
subinermis Kuetz. These three locally dominant species may be 
regarded as forming three societies in the shallow water association. 
The complete list is as follows :— 
Potamogeton natans l.d. P. obtusifolius a. 
Myriophyllum spicatum l.d. Myriophyllum alternifolium f. 
Chara aspera var. subinermis l.d. Nitella opaca f. 
Potamogeton perfoliatus a. 
P. trichoides a. 
N. flexilis var. crassa f. 
Potamogeton heterophyllus f. 
(C). Reed-swamp association. As already indicated the 
reed-swamp occupies the shallower water round the shores forming 
a zonal community characteristic of lowland lochs. 4 The zone is 
sharply divided into two regions—one to the north side of the loch, 
dominated by Phragmites communis Trin., the other to the south 
side, dominated by Carex ampullacea Good, (see map, Fig. 1). 
Moreover, Phragmites is entirely absent on the south side, but on 
the north side the sedge is associated with the reed to a small 
1 F. B. White. “ Flora of Perthshire,” 1898. 
2 J. R. Matthews. “ Notes on Mid-Perth Plants.” Journ. Bot., Vol. 51, 
1913, p. 193. 
3 The first record for Scotland. See note by A. Bennett in Journal of 
Botany, Vol. 41, 1913, p. 336. And for a full account of the distribution of 
this species see A. Bennett, “ Potamogeton trichoides in Perthshire,” Trans. Perth. 
Soc. Nat. Sci., 1913-14 (in the press). 
4 R. and W. G. Smith. “ Botanical Survey of Scotland : Forfar and Fife.” 
Scot. Geog. Mag., 1905, p. 74. 
