XXVI INTRODUCTION. 



and increased by tlie surface drainage into their wide 

 basins, have also great attractions for aquatic species ; 

 and, existing for the most part on private property, are 

 subject to but little disturbance. In size and depth 

 they vary considerably. The largest at Scoulton, which 

 from time immemorial has been a breeding place of the 

 Black-headed Gull (Larus ridibundus) ^ covers with the 

 " hearth" or flat island in the middle, over seventy acres, 

 and is a mile and three-quarters in circumference ; but 

 in some places it is quite possible to wade across to the 

 island. Hingham Mere, within two miles of Scoulton, 

 covers over twenty acres ; Saham, near Watton, twelve 

 acres ; and Diss Mere, in the very centre of that town, 

 five acres — the latter, though the smallest, having 

 an average depth of seventeen and a-half feet. Besides 

 these, in the parishes of East and West Wretham, near 

 Thetford,"^ are several similar pools, varying from about 

 twenty roods to fifty acres in extent, and on some of 

 these waters, which are strictly preserved, Teal, Shovel- 

 lers, and Grarganey, are known to breed, and even the 



* A new and peculiar interest has been excited of late years in 

 these "Wretham Meres, from the discovery through drainage, and 

 the emptying out of the mud, of the remains of " pile buildings" 

 resembling the ancient lacustrine habitations of Switzerland. 

 Professor Newton, in a paper read before the Cambridge Philoso- 

 phical Society in 1862, gives a most interesting account of the 

 discovery made by Mr. Birch of Wretham, when draining " We^t 

 Mere" in 1851, and the " Great Mere" in the same locality in 1856. 

 Both in West Mere, with about eight feet of mud, and in Great 

 Mere, with not less than twenty feet, in some places, hundreds of 

 bones were discovered, consisting almost entirely of the red-deer 

 (Cervus elephus) and the now extinct Bos longifrons, but amongst 

 these was a goat's skull, and the skull of a boar or pig. In this 

 district, also, was made the singular discovery, for the first time 

 in the British Islands, of the remains of comparatively recent 

 Bpecimens of the European Fresh-water Tortoise (Emys lutaria). 

 Vide "Annals and Magazine of Natural History," 3rd series, 

 voL X., p. 224, pis. vi., vii. 



