ment of Agriculture, Beltsville, Md. Miss Emily Bennett, formerly 

 Librarian of the Division of Insects, U. S. National Museum, was 

 extremely helpful in locating certain references needed for the 

 catalogue. The higher categories utilized in this classification are 

 those decided upon by Dr. Metcalf during his work on the cata- 

 logue. 



In this part of the catalogue a method of literature citation has 

 been adopted which differs from that used in the catalogues of the 

 fulgoroid families. References are cited by author, year, and key 

 letter, e.g., Fabricius 1802a. The full reference can be obtained 

 by consulting the Bibliography of the Cicadelloidea, in which 

 authors are arranged alphabetically, and their works chronolog- 

 ically under the author's name. This method eliminates the neces- 

 sity for a complete literature citation in the catalogue proper, and 

 thus saves time, space, and publication costs. It is believed that 

 the revised method will cause no great inconvenience to the reader. 

 Dr. Metcalf himself advocated it under certain conditions, and it 

 is felt that he would have approved its use for his catalogues. 



The Family Euscelidae consists of 390 genera, 47 subgenera, 

 and 2,937 species. The leafhoppers belonging to this family are 

 usually of medium size, never very elongate, and depressed. The 

 head varies in form, but is never foliaceous. Ocelli are present 

 on or near the margin between crown and face, with the lateral 

 clypeal sulci extending to or near them. Antennal ledges are 

 absent. The margins of the genae are seldom strongly sinuate. 

 The antennae are not usually long. The clypellus is not swollen. 

 The pronotum has lateral margins which are usually short and 

 not strongly carinate. In the forewing there are one or more cross 

 veins before the apical cells, the veins are distinct near the wing 

 base, and anteapical cells are present. A number of species feed 

 on grasses, but some feed on shrubs and trees. The predominance 

 of species in northern temperate regions as compared to the 

 Tropics is likely to persist. 



The following classification has been adopted for this family : 

 Family Euscelidae 1 



Subfamily Euscelinae 8 



Tribe Euscelini 10 



Subtribe Limotettixina 128 



Tribe Athysanini 336 



Tribe Thamnotettixini 715 



Tribe Acinopterini __. 1006 



Subfamily Deltocephalinae .._ 1078 



Tribe Cochlorhinini 1079 



IV 



