8 U.S. NATIONAL MUSEUM BULLETIN 261 



considered to have been validly described under the International 

 Rules of Zoological Nomenclature. A number of these new genera were 

 homonyms and all, except the 18 genera mentioned above, were 

 without type designations. 



China (1927d) proposed new names for the preoccupied generic 

 names in Melichar (1926a), and later (1938d) discussed the remainder 

 of the manuscript, as did Dr. V. Szekessy (Melichar 1951a:72). It is 

 my impression, however, that this part of the manuscript is not in pub- 

 lishable condition. China also (1938d) selected type-species for the 

 genera of Cicadellaria which had been characterized only in Melichar's 

 key, except in those cases where the type-species were undescribed. 



Evans (1947a) published a list, prepared by China, of genera with 

 their type-species. Apparently he inadvertently published a number 

 of names of t)'pe-species in the tribe Cicadellini (=Tettigellini) which 

 had never been published by Melichar and which are therefore nomina 

 nuda. 



Oman (1949a) placed the Nearctic species of Cicadellinae (=Tetti- 

 gellinae) into genera, partly on the basis of the male genital structures. 



Morphology 



Cicadelline leafhoppcrs tend to be more heavily sclerotized than 

 specimens of most other subfamilies of Cicadellidae, especially in the 

 tribe Proconiini. As a result, it has been fairly easy to investigate a 

 number of external characters not previously used in cicadellid tax- 

 onomy. Some of these were found to be useful and are discussed below. 



On the head, the relative length and width are of some importance ; 

 length is measured along the median line and width is measured 

 between the eyes (interocular width) or across the eyes (transocular 

 width). The position of the ocelli with relation to an imaginary line 

 drawn between the anterior angles of the eyes (in dorsal aspect) is 

 also of some use, as well as the relative distance of each ocellus from 

 the median line and from the adjacent eye angle. The contour of 

 the surface of the crown is a useful character. There is often a median 

 fovea which may be complete, extending from the posterior margin 

 to the apex, or partial, not attaining the apex. In many species, there 

 is a more or less distinct elevated area along the posterior margin, 

 between the eyes, in the shape of the letter M. In some species there 

 is a short, distinct, longitudinal carina laterad of each ocellus. Occa- 

 sionally the texture and pubescence of the surface of the crown are 

 taxonomically useful. 



The degree to which the antennal ledges are protuberant, in dorsal 



