3 62 



Ltver Kot in North Wales, 1920-21. 



[May, 



too expensive for use on a large scale; (3) one part copper 

 sulphate and two parts kaolin was finally used and was suc- 

 cessful in every way, costing 16s. per acre. By means of (2) 

 and (3) several ditches containing thousands of snails were com- 

 pletely and rapidly cleared, the death rate working out at 98 per 

 cent, to 100 per cent. Subsequent trials with two parts iron 

 sulphate and one part kaolin failed (as did also a trial with 

 a heavy dressing of undiluted iron sulphate, applied by an 

 Anglesey farmer). 



As matters now stand, further extensive field trials on a 

 commercial scale are needed to test the above results. For 

 wet land the writer w T ould favour a 2 per cent, solution of 

 copper sulphate, while for narrow T wet ditches dusting seems 

 advisable, as the mixture is readily made and the apparatus 

 cheap and easy to use. 



Mr. W. H. Savage, M.E.C.V.S., carried out experiments 

 with sheep on the College Farm with both Male fern and anti- 

 mony tartrate, with very considerable success. 



