126 Proceedings of the Royal Physical Society. 



able speed wlieii they choose. When approached within 

 fifty or sixty yards they suddenly stopped feeding, squatted 

 close to the ground, and, after watching me intently for a 

 few moments, sprang with one accord into the air, and were 

 soon out of view. As they rose and flew off, I distinctly 

 made out two different call-notes, namely a low sharp tuck, 

 tuck, which reminded me somewhat of Blackgame ; and a 

 hurried sort of 'purr-t, 'purr-t, very like the note of the 

 Curlew Sandpiper as we hear it on our shores in autumn. 

 The second note seemed to me at the time to bear some 

 resemblance to one of the notes of the Snow Bunting ; but 

 having since renewed my acquaintance with the call of tlie 

 Curlew Sandpiper, I have no hesitation in saying it gives a 

 still better idea of the Sand-grouse note in question. 



XV. Tlie Ancie7it Lakes of Edinburgh. By James Bennie, Esq., 

 Geological Survey of Scotland, and Thomas Scott, Esq., 

 E.L.S., Naturalist to the Fishery Board of Scotland. 



(Read 17th April 1889.) 



The country round Edinburgh is markedly picturesque 

 from the combination of crag and hollow in the more rocky 

 parts, and of softly contoured hillocks with wide open spaces 

 between them, where boulder clay, the peculiar drift of 

 glacial periods, prevails. The crags and hillocks have often 

 captivated the attention of the painter and the geologist, 

 and their forms have been portrayed and their structure 

 described in pictures or essays which have made them 

 famous as illustrations of scenic beauty or geological 

 phenomena. Tlie crags, consisting chiefly of trap-rocks, 

 have been taken as types of volcanic action in open eruptions 

 or injections of lava among sedimentary strata, and the 

 hillocks, composed chiefly of boulder clay, as typical of ice 

 action by ice-sheets or glaciers. The hollows which contain 

 lake marls, silts, or peats, have not been so much studied, 

 partly because such deposits do not obtrude on general 

 observers, and partly because the knowledge to understand 

 them is rarer and more special. But in certain moods these 

 lake marls, silts, or peats have also an attraction not only 



