Mane /tester Memoirs, Vo/. Iviii. (19 14), No. J>. 35 



The Roach is fairly 

 Lenciscns rntilus (Linnaeus.) plentiful in the water. 



On July 1 2th, 19 13, we 

 saw a large fish come to the surface and struggle. We 

 picked it up and it died immediately. Mr. James John- 

 stone, who kindly examined it for us, found that it was not 

 diseased, but its gills were coated with a deposit of phyto- 

 plankton, in which he could recognise some species of 

 Ceratium, Stephanodisats and Anabaena. The mere at that 

 time was " breaking," and the fish had, without doubt, been 

 suffocated by the extraordinary abundance of these plants ; 

 it had been unable to breathe on account of the " water- 

 bloom." Our tow-nettings for that date show that these 

 three constituents of the plankton, and Asterionella, were 

 greatly in excess of their normal numbers. Roach of 

 rather over 2 lbs. are sometimes taken in the mere. 



In a water in which large 

 Salmo trutta Linnaeus. Tike occur there are not 



likely to be many Trout, 

 although introductions have been attempted, and the 

 river Birkin, into which Blackburn's Brook flows, is a 

 good Trout stream. On February i6th, 1895, when the 

 mere was frozen, we saw a fair-sized Brown Trout em- 

 bedded in the ice, and this is not the only evidence that 

 these fish occasionally elude the Pike for some time. 

 When we were trolling for Pike on February 28th, 191 4, 

 Mr. T. Hadfield caught a Loch Leven, a very silvery fish, 

 which scaled 2 lbs. 14^ oz. No Loch Levens have been 

 released in the mere itself, and the dates at which these 

 fish have been turned down by the Bollin Angling Society 

 do not appear to warrant a Trout of this size ; on the 

 other hand, one may have escaped from a stock-pond in 

 Tatton Park and have found its waj- into the mere. If 

 so, this fish must have been in the mere for two or three 



