vi Preface 



Further, there may frequently be doubt as to the identification of the 

 plant suspected of causing poisoning; indeed, in some cases it is 

 possible that the identification rests on the veterinary surgeon or 

 the stockman thinUng a certain plant is the cause. The most 

 complete and systematic account of European poisonous plants is 

 that of Comevin (1887), and references to poisonoiis plants in the 

 ordinary hterature are heavily indebted to him. In so far as the 

 "toxic principles of the plants are concerned, however, his book is in 

 many instances no longer reliable. 



The chemical formulae, quoted for the use of students and research 

 workers, have been checked by considting works by the following 

 authors, the reference to the bibhography being given in brackets: 

 Henry (128), Dunstan (76), Allen (4), Haas and Hill (114), Thorpe (240), 

 Van Eijn (252), Kobert (161), Esser (81), and Beilstein (16). 



Apart from the hterature consulted I desire to acknowledge my 

 great indebtedness to the Board of Agriculture and Fisheries for kind 

 permission to make use of official records; to Mr F. W. (jramett, 

 M.E.C.V.S., for kindly reading the proofs from the veterinary stand- 

 point; to very many Experiment Stations, State Departments of 

 Agriculture, and other authorities in Australasia, America and the 

 Continent of Europe, for assistance given and hterature sent; to 

 Sir David Prain and members of the stafE at Kew for much friendly 

 advice, and aid in consulting the Kew Ubrary; to Sir James Dobbie 

 for permission to spend some time at the Government Laboratories 

 to consult certain volumes; to Mr T. H. Middleton, C.B., Dr E. J. 

 Russell, Professor W. Somerville, Sir Stewart Stockman, Professor 

 T. B. Wood, and others, for information and many helpful suggestions ; 

 to my friend Mr W. A. Whatmough, B.Sc. (Lond.), for many sugges- 

 tions and kindly reading the proofs; and to my colleague Mr W. R. 

 Black for invaluable help in preparing notes, checking data and reading 

 proofs. To all these, and many others who are not mentioned by 

 name, I tender my sincere thanJis. 



For any shortcomings I crave the indulgence of my readers, only 

 requesting that they be friendly enough to spare a moment to call 

 my attention thereto. 



H. C. LON(]t. 



SUBBITON, 



October, 1916. 



