STONEFLIES, ALDER, SMUTS, ETC. 289 



Houghton on the Test. I do not think, however, 



that it is at all well taken generally on that river. 



On some north-country streams I am told that an 



imitation of it is quite a useful pattern. A moderately 



good imitation is given in " Dry- Fly Entomology," 



but I think the colouration generally is too orange 



in hue. 



SIALID^ 



One genus only is comprised among the British 



Sialidae and this the well-known 



Alder. alder (Sialis lutarid) is one of 



the commonest of insects seen 

 at the river-side from the middle of May to the middle 

 or the latter part of June. There is a second 

 species called S. fuliginosa, and McLachlan, writing on 

 it in the " Transactions of the Entomological Society " 

 in 1868, says that these two species {S. lutaria and S. 

 fuliginosa) can only be distinguished by the presence 

 in the latter species of one transverse nervule in the 

 anterior wings. 



Angling writers have so glorified the alder that one 

 is almost compelled to give some space to it, although, 

 as will be seen by the following brief sketch of its 

 life history, it is at no time during its life in the 

 winged stage voluntarily on the water, and therefore is 

 not likely to form an important part of the food of the 

 rising fish. I do not want to exaggerate this state- 

 ment in any way. If it is by chance blown on to 

 the water and comes down over a feedinof fish 

 struggling on the surface, it will of course be taken. 



