ON RAPID STREAMS. 131 



them together, as the mode of using them is pre- 

 cisely similar. I know but of one difference, and 

 that is, that the fern web is a softer and more 

 delicate bait more easily whisked off than the 

 beetle, and consequently requires more care in its 

 usage ; in this respect being an intermediate step 

 between the soft down-hill fly and the hard- cased 

 beetle. The fern web I need scarcely pause to 

 describe ; everybody knows the little insect, 

 which, in the end of May and through June and 

 July, may be found on the ferns ; but the cow- 

 dung beetle is by no means so generally known ; 

 its name bespeaks something disagreeable, and 

 you need a boy to collect them for you. They 

 soon cleanse themselves if put into a tin in good 

 numbers, by rubbing against one another. The 

 beetles are a little larger than fern webs; have 

 their wing cases perfectly black and shining, 

 dense and strong, and are thicker set, shorter and 

 brqader in figure than the fern web ; their bel- 

 lies and under surface beneath the wing and 

 Covers are perfectly black; they are found in 

 recent cow-dung that of about two to four days' 

 exposure, usually lying beneath the dung on the 

 ground, though often in the dung itself. An- 

 other beetle, something resembling it, is also 

 found in the same dung ; usually they are toge- 

 ther but this other beetle must be carefully dis- 

 carded ; he may be known by his being less dense 

 and black in the cases of his wings, by his greater 

 length of body, by his belly being reddish, and 

 the parts under the wing light-coloured. I have 

 K 2 



