NATURAL HISTORY OF SELBORNE. 87 



of the wood-wren, common wren, or the willow warblers, rather 

 than the thrushes. It is generally made of moss and grass 

 tightly woven together. One in my collection is composed 

 mainly of grass and the stalks of sedges, and is thickly lined 

 with dead leaves. The eggs are uniformly white when blown, 

 but before this have a beautiful tinge of salmon colour. The 

 young dippers are curious little birds, and take to the water at 

 a very early age. The eggs are of a more transparent white 

 than those of such birds as the wood-pigeon or the owl, and 

 number from four to six." 



"W.vTEK-OusEL, p. 112. This pretty little bird is accused of 

 eating salmon and trout eggs from the natural spawning-beds. 

 I am strongly of opinion he never does anything of the kind. 

 Here is a good witness in the bird's favour. Mr. J. H. Horsfall, 

 of Leeds, writes me : " I have made, at your request, a most 

 careful examination of the bird, from the stomach downwards. I 

 was pleased to find the gizzard (which is by no means very mus- 

 cular) quite full. I placed it in a vessel of clean water, divided it 

 in half, and emptud out the contents, the whole of which I passed 

 in detail under the object-glass of a microscope. I cou!d not find 

 the least trace of fish ova; I looked especially for the horny egg- 

 cases, for these would be the most likely portions of the egg to 

 escape digestion, but I could not find any appearance whatever 

 of them. The contents of the gizzard consisted entirely of the 

 hard external cases of water insects, portions of the legs with the 

 hooks attached, and broken fragments of other portions of their 

 bodies, intermixed with some vegetable structiire and several 

 small fragments of gravel and transparent quartz. 



" Twenty fell to my gun, just as they emerged from the spawn- 

 ing-beds, every one of which I at once opened from bill to gizzard. 

 On examination, both before and after washing, with the naked 

 eye and under the microscope, I could not in one single instance 

 discover a trace of ova, neither of case of ova, nor of the olea- 

 ginous matter which forms the contents of the case ; instead of 

 this, I found the stomach full of the larvae of flies, whole and in 

 fragments, and always more or less of fine sand. About this date 

 I heard of the destruction of ova in the boxes at Stormontfield 

 by the lame of the stonefly, and it immediately occurred to me 

 that I was destroying a most efficient assistant, and that the 

 water-ousel was one amongst the many exquisite links con- 

 stantly presenting themselves to the student of the natural his- 

 tory of salmon and trout. During the formation of the spawn- 

 ing-bed, the salmon turns over gravel, in the interstices of 

 which lie the larvae of aquatic flies, to which the water-ousel is 

 VOL. II. 



