LAWSON: KANSAS CICADELLIDyE. 7 



done because of what seem to have been doubtful determina- 

 tions. We have endeavored to exclude every species of the 

 occurrence of which in the state we had any doubt. Accord- 

 ingly we have practically confined ourselves to the species rep- 

 resented in the Snow collection at the University of Kansas. 

 There are other collections in the state which will yield addi- 

 tional records. It is our purpose to examine these as soon 

 as possible and add to this list. Among others, the collection 

 of the Kansas State Agricultural College and Crevecoeur's col- 

 lection will yield further records, as will the private collec- 

 tions of Prof. Herbert Osborn and others who have collected 

 in the state. These all should have been included in this paper, 

 but a combination of circumstances seems to have made it 

 impossible. 



We have, however, included in the keys, and given descrip- 

 tions of a goodly number of species, which, judging from 

 their known occurrence, are likely to be found in the state. 

 We believe this will add to the usefulness of the paper. 



The question of bibliographies has proved to be a trouble- 

 some one. It w^as finally decided to give a rather full bibliog- 

 raphy for each species, but to omit, except in cases where the 

 bibliography was brief, the mere lists and those papers which 

 do not distinctly add to our knowledge of the group. Ac- 

 cordingly we have chosen our bibliographies with a view to 

 showing the course of the synonomy of the species, and to 

 those papers which give information as to life history, food 

 plants, economic importance and control, and those which give 

 figures illustrating the species. In addition we have tried 

 to include a list of the papers which have appeared since the 

 publication of Van Duzee's catalogue. 



