1922] Olse?i: Cicadella of North America 355 



Kolla similis Walker, 1851, has been included in this genus 

 as it seems to compare better with the type Cicadella viridis 

 Linnaeus than it does with the type Kolla insignis Distant, 

 although I have never seen specimens of the latter type. Taking 

 this species out of Kolla may possibly improve that genus, the 

 characters of which at their best are none too good for our 

 known, North-American species. 



Cicadella circellata Baker, 1898. It is quite possible that 

 Signoret's atropunctata is the same as this; further study is 

 therefore warranted, and particularly of material from Brazil. 



Through the courtesy of Mr. Edmund Gibson the writer has 

 had the privilege of studying a collection of specimens in this 

 genus from the United States National Museum. Dr. F. E. 

 Lutz kindly gave permission to examine the material in the 

 collection of The American Museum of Natural History, and 

 Mr. H. G. Barber turned over his very valuable collection to 

 my disposal. Mr. E. P. Van Duzee, Dr. E. D. Ball, and others 

 have kindly assisted with desirable specimens and were kind 

 enough to answer correspondence on this subject. To these 

 gentlemen I am very grateful for their unfailing assistance and 

 to them I wish here to express my sincere appreciation. These 

 collections, together with my own, accumulated material, have 

 made this paper possible. 



Cicadella viridis Linnaeus, 1758 



This species has been included in our faunal list on the 

 strength of a single record by Provancher, 1889. The specimen 

 was seen in Provancher's collection at Quebec, Canada, and 

 examined by Van Duzee, 1912. Its identity cannot be ques- 

 tioned. This record is rather unique for such a widely distrib- 

 uted species of the Old World. It appears in most of the Euro- 

 pean lists as a common species abundantly collected; it is 

 reported from the British Islands (Edwards 1888), across the 

 Danish peninsular (Jensen-Haarup 1915-1920), through Rus- 

 sia (Oshanin 1907), to Japan (Onuki 1901); in Europe as far 

 south as Italy (Ferrari 1895). It occurs in damp, grassy loca- 

 tions along edges of swamps and meadows. 



Had this species once gained foothold and become estab- 

 lished here, there is every good reason to believe that it, like 

 so many other Hemiptera, would find but little difficulty in 

 maintaining itself, if not actually spreading. At least we might 



