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pean fauna would appear. Comparisons of this character are, how- 

 ever, of little value without the study of more extensive material 

 than we now possess. The first duty of our entomologists is to 

 make known the numerous species occurring in their country; for, 

 until this is done, we can have no accurate knowledge of our own 

 fauna or of its relations to those of other countries. Then, too, 

 will there appear a more general interest in these small and despised, 

 albeit frequently beautiful creatures; and collectors will account 

 them worthy of preservation when inadvertently taken by them 

 while in quest of larger game, and students will not, as at present, 

 be obliged to solicit in vain for exchanges, or go in person for the 

 desired material, or do without it. 



A few of the terms and measurements employed in the follow- 

 ing descriptions possibly call for a word of explanation. The length 

 of a specimen is measured from the tip of the head to the apex of 

 the elytra, or of the abdomen if it projects beyond the elytra. 

 Width of the head includes the eyes; width of the pronotum is 

 supposed to be measured across at the widest point, generally at the 

 lateral angles, or the angles between the lateral and latere- posterior 

 margins. In the nomenclature of the venation I have adopted that 

 employed by Dr. Fieber as in all respects the most convenient and 

 satisfactory. In Fieber' s scheme for separating the genera of the 

 JassidcE the element of the neuration of the elytra and wings is given 

 a very prominent position, and I think justifiably so. notwithstand- 

 ing the fact that it is subject to frequent and considerable variations. 

 In all the Jassidcc the variation in the form of the genital pieces 

 furnish very important characters for distinguishing the species, but 

 in these descriptions I have made use only of such parts as can gen- 

 erally be seen without mutilating the specimen. In the male they 

 are as follows: The Plates are two flat, or slightly convex, pieces 

 placed on the ventral surface, with their inner edges in contact so 

 that together they generally form a more or less regular triangle, 

 which may be short and blunt, or long and narrow, with the sides 

 either convex or concave; on the edge they are generally fi-inged 

 with long hairs, and there is at times a submarginal row of stouter 

 spines. On the base of the plates is a triangular, rounded, or short 

 and transverse piece called the Valve; it varies much in shape, and 

 the apex may be acute, obtuse, or emarginate. Beneath the plates 

 as viewed from below, are two long, more or less slender and curved 

 pieces termed the Styles; they are rarely mentioned, as they are 

 generally concealed from sight beneath the plates. Still farther 

 behind these, and really forming the apical segment of the tergum, 



e 



