1909-10.] Flora of Scottish Lakes. 169 



There is no boat on any of the three last-mentioned lochs, so that it is 

 impossible to say anything about their submerged plants except such as 

 could be seen from the shore, or washed there, or gathered by swimming 

 after them. Besides the plants already enumerated the following species 

 were more or less common to these three lochs : — Littorella lacustris, Lobelia 

 Dortmanna, Myriophyllum alterniflorum, Fontinalis antipyretica, Chara 

 fragilis, var. delicatula, Castalia speciosa, Potamogeton polygonifolius, 

 Equisetmn limosum, Carex Goodenovni, Ranunculus Flammula, Eriophorum 

 vaginatum, Juncus acutiflorus, J. effusus, Cardamine pratensis, Montia 

 fontana, var. minor, Hydrocotyle vulgaris, Blindia acuta. Sphagnum 

 intermedium, S. cymbifolium, Philonotis fontana, Aulaconmium palusti-e, 

 Polytriclmm commune, P. gracile, Hj^pnum commutatum, H. revolvens, 

 H. scorpioides, H. cuspidatum, H. fluitans, Webera nutans, Bryum bimum, 

 B. pallens, B. argenteum, Ceratodon purpurens, Rhacomitruim aciculare, 

 Scapania undulata, Pellia epiphylla, and Diplophyllum albicans. 



Harperleas Reservoir is situated on the Lomond Hills, at an elevation 

 of 848 feet above sea level. It is about h mile long, and is of an irregular 

 shape, with clear but somewhat peaty water. It has been formed by the 

 construction of a long dam at the east end, and there the maximum depth of 

 41 feet occurs. The south shore is either stony or muddy, and at some 

 places the bank enters the water without the intei-vention of a shore. At 

 the north and west the shore is flat, and muddy or peaty, and is covered 

 with a luxuriant vegetation, whilst there are very few plants at the south 

 shore, and none along the dam. A zone of Equisetum limosum, behind 

 which are Carex rostrata and Juncus eftusus (fig. 110), extends along the 

 greater part of the north side. The Equisetum is intermingled with 

 Littorella lacustris, which also runs up the shore and forms a dense sward 

 in some places. Occasionally considerable areas of exposed mud were 

 covered with Juncus fluitans, which was reverting to the terrestrial type — 

 J. supinus — which it somewhat resembled. Other normally submersed 

 plants were assuming a terrestrial habit and forming a meadow-like sward 

 upon the exposed shore, particularly Ranunculus aquatilis, Heleocharis 

 acicularis, Pol3'gonum amphibium, Potamogeton polygonifolius, and P. 

 heterophyllus. The normal aquatic form of the last mentioned was very 

 abundant at this loch, and those plants left upon the exposed mud were 

 developing new shoots with aerial leaves similar to the coriaceous floating 

 ones but smaller, the shoots with thin submersed leaves having completely 

 withered away. At the north-west end a portion of the shore presented a 

 remarkable appearance through being covered with dead tussocks of 

 Molinia crerulea, which had been drowned during some period when the 



