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XVI, Prcdaccous Insects and their Prey. By Edwakd B. 

 PouLTON, D.Sc, M.A., LL.D. Princeton, F.R.S., 

 Hope Professor of Zoology in the University of 

 Oxford, Fellow of Jesus College, Oxford. 



PART I. 



Predaceous Diptera, Neuroptera, Hemiptcra, Ortho'ptera, and 



Coleopitera. 



[Read June 6th, 1906.] 



Contents of Part I. 



PAGE 



Introduction to Part I 324 



I. DIPTERA 329 



A. ASILID^ AND THEIR PREY 329 



Proportions of the Sexes 359 



Analysis op Prey 359 



Conclusions as to the Habits of the Species and 



Genera of Asilid^ recorded in this Memoir . 364 



I. DASYPOGONIN^ 364 



Dioctria 364 



The Prey of Dasypogon diadema . . . 365 



TJie Courtship of I)asypogon{Selidopogon) diadema 366 

 Dasypogon {Selidopogon) diadema^ a mimic of its 



m,ost conspicuous victims ..... 368 



Remaining Genera of the Dasypogmiinx . . 369 



II. LAPHRIN^ 370 



///. ASILINjE 370 



The Prey of Promachus . . . . .371 



The Prey of Alcimus and allied genera . . 372 



Philonicus, Patnponerus and Asilus . . . 373 

 An observation on the cryptic attitude of Asilus 



crahroniforrais during prolonged rest . . 374 



Lophonotus, DysmacMis, and Eutolmus . 374, 375 



The Prey of Machimus .... 375, 376 



Neoitamus and Epitriptus .... 375, 377 



Mimicry in Asilid.e recorded with Prey . . 377 



B. EMPIDiE AND THEIR PREY 379 



Analysis op the Prey op recorded Species op 



Empid^ and op the Sexes op the Captors . 386 



Proportion of the Sexes ..... 388 



Female Empidae with Prey captured in coitu . 388 



The choice of Prey by Empidee {Hybotinae, Empinee 



and Tachydrominse) .... 388, 389 



C. PREDACEOUS DIPTERA OTHER THAN ASILID^E 



AND EMPIDj;, WITH ^THEIR PREY . . .391 



Dolichopodldse, Anthomijidae, and Gordyluridse . 393 



The Prey of Scatophaga ..... 393 



Ochromyia jejuna ...... 394 



The Prey of the larval Syrpjhid fiy, Xanthandrus 



comtus {Melanostoma hyalinatum,) . . . 396 



TRANS. ENT. SOC. LOND. 1906.— PART III. (jAN.) 22 



