164 Proceedings of the Royal Society of Edinburgh. [Sess. 



of which it sinks in order to hibernate, whilst the Polj^gonum grows best 

 in comparatively shallow water. (2) Owing to the luxuriant development 

 of the floating leaves of the Polj^gonum, which obstruct the free access of 

 light to the water below, the Ceratophylluin is not able to thirve in this 

 darkened area, and consequently becomes extinct at the margin of the 

 Polygonum association. Notwithstanding its absence in a few small areas, 

 the quantity of Ceratophyllum in this loch is extraordinary. Equally 

 striking is the flora of the bog at the west end. Considerable portions of 

 it are covered with associations of Menyanthes trifoliata, the individuals of 

 which are so closely compacted that no other plants can thrive amongst 

 them. Ranunculus Lingua is also very abundant and grows in large patches, 

 the vivid yellow of its masses of flowers aftbrding an agreeable tone to the 

 sombre green of the tussocks of Carex paniculata (fig. 103), which dominates 

 the greater portion of the bog. 



Besides those already mentioned, the following plants occur here : — 

 Callitriche autumnalis, Potamogeton Zizii, Zannichellia palustris. Ranunculus 

 circinatus, Myriojjhyllum spicatuin, Lemna minor, L. trisulca, Cladophora 

 crispata, Carex rostrata, Heleocharis j)alustris, Cicuta virosa, Sparganium 

 simplex, S. ramosum, Epilobium hirsutum, Ranunculus Flammula, Caltha 

 palustris, Myosotis palustris, Galium palustre, Spiraea Ulmaria, Mentha 

 aquatica, Juncus eflusus, Phalaris arundinacea, Montia fontana, etc. [Scirpus 

 sylvatica, close to the loch. — J. M'A.]. A number of Bryophytes occur about 

 the banks and on fallen timber, particularly at the south and west sides, 

 but as these are chiefly forms that grow in damp woods and similar places 

 they cannot be named as belonging to the loch. 



Loch Fitty is situated amidst a mining and agricultural district 3 

 miles west of Cowdenbeath. It is a mile long by ^ mile wide, is at an elevation 

 of 413 feet above sea level, and has a maximum depth of 17 feet. The water is 

 clear but it has a flat, dead appearance, especially so in autumn when the 

 abundant vegetation, particularly the Characeae, is decomposing. A fine 

 tow-net used in the middle of the loch at the end of September caught a 

 very pure collection of Asterionella formosa. Many of the submersed 

 plants were heavily incrusted with lime, which proves the presence of that 

 substance in the water. Some plants, e.g. Potamogeton Zizii and P. 

 perfoliatus, were so weighted with this substance that many of them were 

 lying on the bottom instead of rising up to the surface. The shore at the 

 north side is stony, gravelly or sandy, and almost destitute of marsh plants. 

 At the south side a portion of the shore is composed of a bank of shale, 

 which has been thrown out from an adjacent mine, and a number of aquatic 

 plants occur in the pools and little bays formed by the irregularities in this 



