GEx\ERAL REMARKS. 



The present paper deals with such members of the greai 

 Chalcidoid series as are connected with leaf-hoppers, but ex- 

 cludes the Mymaridae, which have been treated of already in 

 Part VI. of this Bulletin. I had intended to include all the 

 species that were bred by us during our studies of* leaf-hoppers 

 in Australia, and further to describe the few species of Ichneu- 

 mon flies that were connected with certain of the natural ene- 

 mies of Homoptera, but these and a few of the Chalcids I have 

 decided to leave at present undescribed. Of some of these the 

 material for study is in'adequate, and of others the 'habits were 

 not sufficiently closely examined as to warrant their inclusion 

 in this study. Further, to any one acquainted with the diffi- 

 culties presented by these most extensive series of insects, and 

 with the fact that most of the species that we obtained, belong 

 to some of the largest and most difficult families in these series, 

 while no semblance of a classified reference collection exists in 

 the Hawaiian Islands, it will not be surprising that I have re- 

 frained from dealing with a few of the most obscure and diffi- 

 cult forms. Most of these, however, I shall refer to incident- 

 ally in the following remarks: 



HAB'ITS OF THE PARASITES HERE CONSIDERED. 



We may divide the Chalcid parasites connected with leaf- 

 hoppers into five classes according to their habits. 



(i). Direct enemies of leaf-hoppers or primary parasites, 

 i. e., those which attack these in one stage or another, from the 

 egg to the adult. 



(2). Species beneficial to leaf-hoppers, or secondary para- 

 sites, i. e., those which destroy the direct enemies or primary 

 parasites. 



(3). Species which are indirectly enemies of leaf-hoppers, or 

 tertiary parasites, since they destroy the secondary parasites. 



(4). Species which are beneficial to leaf-hoppers, since they 

 are parasites of predatory insects that destroy leaf-hoppers. 



(5). Species which are indirect enemies of leaf-hopper since 

 they destroy the preceding. 



In the first of these divisions if we exclude egg-parasites, 



