Washington, D. C. April, 1927 
A STUDY IN HYPERPARASITISM, WITH PARTICULAR REFERENCE TO THE 
PARASITES OF APANTELES MELANOSCELUS (RATZEBURG) 
By C. F. W. Musssseck, Hntomologist,and S. M. Douantan, Assistant Entomol- 
ogist, Gipsy Moth and Brown-tail Moth Investigations, Bureau of Entomology * 
CONTENTS 
Page Page 
AMtLOCUIChION See tern eee Son Seve eee a. 82 1 | Biology of the hyperparasitic species con- 
Extent of hyperparasitism_--___----_--------- 2, cerned in the parasitism of Apanteles melan- 
Systematic position of hyperparasites__-_---- 3 oscelus—Continued. 
Specie hostrelaions= =.= = se 4 @halleid otc cere as ese ym ee emer 18 
Feeding of adult hyperparasites__________-_-- 6 Chalcididaereses 22s saa ees eee 18 
arinenoenesis-t eas: sah sah ora NSE 7 Callimvomid {eens eee eee eae 19 
Life cycle of Apanteles melanoscelus_-.-_------ 8 IDOH AOI BY eee ee eS 20 
Methodsiemployedss 6 a2 See eee 8 Hupelimid aes esas kee eee 21 
Data obtained from field collections of co- ONC VEEIGACS Sao tose ee Se il 25 
.coons of Apanteles melanoscelus__.--------- 10 Pieromalidaec: 225. See oan age 25 
Biology of the hyperparasitic species con- MAST dae Vee as os ee See ye ee 29 
cerned in thé parasitism of Apanteles melan- Hulophidaeriv ssa eee ee 29 
OSCGLIUS Sea Bk ite ners ex Eat ES Ss 12 Coleopterase: fs20 eee ay ne eee pero 
lichnenmonid ae s2= = 2-2 ee 2 12 Cleridae sss. oo oe ee eee 32 
CONES A DLE OTS YS) ee ak alg A a ee ae eee TU VERE 0 0 a Wm ee seep een ON gE cS apt 32 
Ophionindets* = 25, Ss sass 5s 18°) SLiterature citedt 2312s -f. eee sets eee 34 
INTRODUCTION 
Insect hyperparasites, or parasites that attack other parasites, 
have often seriously interfered with the progress of studies in the 
biological control of injurious insect species and with the institution 
of this method of control on a practical basis. A primary parasite, 
imported for the purpose of combating an introduced injurious insect, 
may be overwhelmed by hyperparasites before it can succeed in 
firmly establishing itself in the region to which it has been trans- 
ported. Im any case the hyperparasites will certainly delay very 
considerably the time when such primary parasite becomes suffi- 
ciently abundant appreciably to check the pest for the control of 
which it was introduced. Hyperparasitism is of such general occur- 
rence that it will be encountered in one form or another in practi- 
1 The writers wish to record their indebtedness to A. B. Gahan and R.A. Cushman, of the Bureau of 
sntomology, for the determination of most of the species of hyperparasites discussed in this bulletin; to 
P. B. Dowden for valuable assistance rendered in the course of the work; to A. F. Burgess for his criticism 
of the manuscript; and to W. N. Dovener for the drawings reproduced in this bulletin. 
33012—27——1 
