176 THE FEESH- WATER LOCHS OF SCOTLAND 
Polygonum Persicaria, L., VL, VIL Sometimes abundant on the 
shores of lowland lochs. 
Polygonum aviculare, L., VL, VIL Sometimes overgrows the drier 
parts of the shores of lowland lochs. 
CERATOPHYLLACE.E 
Ceratophyllum demersum, L., VIL Otterston Loch is the only 
record for the lakes under consideration, and it grows there in 
extraordinary abundance. 
AMENTIFER^ 
Alnus glutinosa, Gsert., L, II., III., IV, V., VL, VII. Frequent. 
Betula glutinosa, Fries^ L, II., III., IV., V., VL, VII. Frequent. 
Myrica Gale, L., L, IV., V., VI. Frequent. 
Sahx aurita, L., I., IL, III., IV., V., VL, VII. Frequent. 
The above four species are the most dominant trees or shrubs 
that occur naturally in wet places about the shores of lakes. 
Many other species and genera occur, especially about the 
lowland lakes, but mostly on drier ground. These and the 
damp-loving species of Salix, Populus, etc., that are found, 
generally bear evidence of having been planted for shelter, 
ornament, or other purposes. 
HYDROCHARIDACE/E 
Anacharis Alsinastrum, Bab.^ VII. Particularly abundant in Loch 
Leven, but less so than formerly on account of the raids made 
against it by the angling authorities. [VI. , Monreith Loch, 
—J. M'A.] 
IRIDACE^. 
Iris Pseud-acorus, Z., I., IL, III., V., VL, VII. Frequent ; often 
overgrowing a considerable patch of littoral marsh, but rare 
about the hill lochs. 
ALISMACE.E 
Alisma Plantago, L., I., IL, V., VL, VII. Rare in I. and II. , but 
often abundant about the lowland lochs of the other Areas. A 
curious submerged form occurs at Loch Gelly, and a weak, 
narrow-leaved form was found at Loch Fiart. 
Alisma ranunculoides, L., HI., IV., V., VI. , VIL V^idely distributed, 
but seldom abundant. Dwarf forms about 1 J inches high occur 
in the exposed sandy shores of Loch Leven and other places. 
An entirely submersed form about 3 inches high with quite 
subulate leaves is occasionally found and is quite abundant at 
