﻿GEXERAL ACCOUNT OF WORK DONE IX AUSTRA- 

 LIA, FIJI AXI) THE UXITED STATES. 



Tlie material on which this liulletin, entitled "Leaf-Hoppers 

 and Their Xatural Enemies," is based, has been derived from 

 various localities and sources, which are herewith specified. 



(i). In 1903 Mr. Koebele made extensive observations on this 

 sul)ject in Xorth America, chiefly in the states of Ohio and 

 California, and sent a large amount of living material to the 

 Hawaiian Islands. 



(2). In 1904 Mr. Koebele accompanied by the writer visited 

 Australia and a still larger collection of leaf-hoppers and their 

 enemies was made in that country. 



(3). In the early months of 1905, after I returned to these 

 islands, Mr. Koebele spent a short time in h^iji. continuing .Vus- 

 tralian studies. 



(4). For several \ears the sugar-cane and some other leaf- 

 hoppers and their enemies have been under close observation in 

 the Hawaiian Islands, and a collection of these has been made. 



I will now make some remarks on these various expeditions, 

 showing what was achieved in each case. 



KOEBELE'S MISSION TO THE UNITED STATES. 



Mr. Koebele's researches in ( )hio in 1903 were ]irimarily un- 

 dertaken on information kindly given him by Dr. L. ( ). ITow- 

 ard, of the Department of Agriculture. A short time previously 

 Mr. Otto H. Swezey had discovered that certain leaf-hoppers 

 in that State were attacked In- Hymenopterous parasites, an(' 

 Mr. Koebele was notified of this fact by the chief of the ento- 

 mological staff at Washing-ton. Mr. Koebele's investigations 

 resulted in the discovery of many such parasites , belonging to 

 the family Dryinidae. Hie appearance of these parasites is well 

 exemplified l)y the "Fairchild ])arasite" (Echtlirodclphax fair- 

 cliihfii) of the cane leaf-hopper, now so familiar to most Ha- 

 waiian cane-planters. 



In addition to these Dryinidae, the little Mymarid egg--i)ara- 

 site of Liburnia {.iiiagnis cohiiiibi) was discovered, and also the 

 common presence of the minute Stylopids of the genus FJciiclnis 

 and others. Finally there was procured a single pu])arium of a 



