452 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 3 



phenomenon, Mr. Fiske has performed a signal service. It seems 

 worth while to present some concrete examples which have come to 

 the notice of the writer, in order to make this interesting phase of 

 parasitism more widely understood. Brief perusal of the records of 

 the Southern Field Crop Insect Investigations seems to show the ex- 

 istence of a number of important phases of superparasitism in addi- 

 tion to those brought out by Mr. Fiske' s work on the gypsy moth 

 parasites. 



An effort has been made to classify the various examples which have 

 been gathered in such a manner as to show in how many ways the 

 parasites may interact upon each other, even in as simple a parasite 

 problem as the boll weevil presents. There are many other branches 

 of entomological research where parasite conditions are far more 

 complicated than in the instances herewith cited. 



Insect parasitism of weevils may be classified as follows: 



( Simple j Endoparasitism 



1. Primary I \ Ectoparasitism 



( Multiple Endoparasitism 



Hyperparasitism 



2. Secondary , „ 



( Superparasitism 



These different phases may therefore be defined in couplets. 



Primary parasitism is an original parasitic attack upon a host. 



Secondary parasitism covers all subsequent attacks by parasites. 



Simple parasitism is the attack by a single individual. 



Multiple parasitism is the normal simultaneous attack by a num- 

 ber of individuals of the same species. It is probably the result of 

 polyembryony in manj^ cases. 



Endoparasitism is the internal attack of a parasite. 



Ectoparasitism is the external attack of a parasite. 



Hyperparasitism is the normal attack of a parasite species upon 

 another parasite species. 



Superparasitism occurs when a normally primary parasite attacks 

 a host already parasitized, and the result is that the latest comer 

 generally attacks its predecessor. 



Predation complicates parasitism many times and in fact brings 

 about the same results as superparasitism; in other words, a struggle 

 between forces working for the same end — the control of the host. 



The following examples have been collected to illustrate each of 

 these phases or their combinations : 



Simple ectoparasitism is the commonest phase of parasitism upon 

 external feeding weevils. Some of these parasites are quickly fatal 

 while others are much less so. Bracon mellitor Say, Catolaccus sp., 



