1909-10.] Flora of Scottish Lakes. 163 



Veronica scutellata, V. Beccabunga, Cnicus palustris, Sagina nodosa, Bartsia 

 Odontites, Stachys palustris, Deschampsia caespitosa, Achillea Ptarmica, 

 Scutellaria galericulata, Gnaphaliuin uliginosum, Grimmia apocarpa, var. 

 rivularis, Eurhynchium ruscifonne, Bryum argenteum, Hypnuin cuspidatum, 

 H. lipariuin, etc. This a long list of plants for a small loch of comparatively 

 recent formation, and it will be noticed that the greater number of species 

 are those of the marsh zone. A considerable number of water- fowl resort 

 to this reservoir, and they are doubtless responsible for the introduction of 

 so many plants, which, moreover, find the shores a suitable liabitat. 

 Scutellaria galericulata, for instance, is not a common plant at the lochs of 

 Fife, but in marshy ground, adjoining the seashore, about 2 miles south- 

 west of Aberdour, it grows in great abundance, and possibly it was trans- 

 ported from there to the reservoir by gulls, etc. 



On the top of Balcam Hill, which adjoins this reservoir, tliere is a small 

 pool about 12 3'ards long, containing over twenty species of aquatic and 

 marsh plants, two of which, namely Glyceria fluitans and Potamogeton 

 natans, do not occur in the reservoir below. 



Otterston Loch is a small shallow sheet of water, 2 miles west of 

 Aberdour. It is closed in by low hills and is entirely surrounded by 

 luxuriant deciduous trees, which also cover a small island in the middle. 

 The water is not peaty, and, although clear, it has a dead, stagnant appear- 

 ance. The loch is an ornamental sheet of water to Otterston House, which 

 stands upon its north side, whilst the public road from Aberdour adjoins it 

 on the north-east. Except on the west side, where there is an extensive 

 and treacherous bog, the loch is bordered nearly everywhere by low walls 

 or grassy banks (figs. 100-102), so that there is practically no shore, but in 

 several j)laces marsh vegetation overgrows the banks. At the west end 

 the mud at the bottom is deep, black, and fetid ; at the east end there is 

 much less mud, and tliere some parts of the margin are sandy, or a narrow 

 zone of stones may even occur (i\g. 102). Ceratophyllum demersum is so 

 abundant that the loch is almost choked with it, and in summer, when the 

 plants are at the surface, the manipulation of a boat over the water is a 

 matter of some difficulty. Doubtless many plants that otherwise would 

 thrive in this loch are excluded by the Ceratophyllum, which appears to be 

 gradually extending, for I have noticed that Ranunculus Baudotii, which 

 was abundant at the east side of the loch in 1903, had in 1908 become 

 almost extinct by the extension of the Ceratophyllum. The latter, how- 

 ever, is not able to hold its own in the marginal zone against the Polygonum 

 amphibium which grows there (figs. 100 and 101), possiljly for two reasons. 

 (1) The Ceratophyllum is favoured by water of some depth, to the bottom 



