18 THOMAS SAY FOUNDATION 



identifying several European species occurring in our 

 fauna, and by the donation of paratypes of his species. 



Summary. 



One hundred and forty-five species and varieties, 

 belonging to sixteen genera, are described in the pres- 

 ent paper, and the genitalia are figured in 138 cases; 

 other figures bring the total number on the plates 

 to 170. 



A list of the included species is given in the ex- 

 planation of the plates. The number assigned to a 

 species in the text is in every case the same as the 

 number of the figure or figures illustrating it. 



In a large number of the species, the female has 

 not been described ; and it is possible that some errors 

 have occurred in identifying females with the wrong 

 male, as but few pairs collected in copula exist in col- 

 lections. 



'Not only is there much to be done in studying 

 the females, but there are beyond doubt many spe- 

 cies yet to be described, especially from tropical and 

 subtropical regions. Nothing is ever final in tax- 

 onomy. 



Only species seen by the writer are included. 

 The numerous old names which cannot be elucidated 

 at present (their types being lost or scattered in Euro- 

 pean museums) are to be found in the Catalogue of 

 1905, and are not repeated here. It is impossible to 

 follow any other course than to ignore them, or else 

 w^ait many years with the group in liopeless confusion. 

 The latter course seems especially undesirable since a 

 real key to the species has l)een found in the genitalic 

 characters. 



