TABLE OF CONTENTS 



Page 



Introduction lo 



Pali 1 



General Discussion of the Family. 



Historical Account. Systematic Position. Phylogeny. Geographical Dis- 

 tribution. Geological Distribution 12 



General Characters. 



I. The Egg — Description. Characters Available for Classification. Date 



of Oviposition. Duration in Egg Stage. Where and How Deposited 16 



II. The Larva — General Description and External Anatomy of Several 

 Kinds of Larvae. Characters Available for Classification. Date of Appear- 

 ance. Duration in Larval Stage. Haunts or Habitats. Food. Charac- 

 teristic Methods of Feeding. Methods of Defence. Protective Coloration. . 17 



III. The Pupa — Description. Pupal Respiration. Characters Available for 

 Clas.sification. Date of Pupation. Duration in the Pupal stage. Place of 

 Pupation. Defensive Structures. Pupa within the Puparium. Emergence 



of Adult 2S 



IV. The Adult — Characters of the Family. Mouth-parts. Secondary Sex- 

 ual Characters. Characters Available for Classification. Date of Appear- 

 ance. Haunts or Habitats, Habits, Food, etc. Methods of Natural Pro- 

 tection, Miinicr}-, etc 31 



An Evolutionary Table of Larval Habits 38 



Biological and Ecological Relations and Economic Importance of the Larvae. 42 



Ecological Relations and Economic Importance of the Adults 48 



Enemies 50 



Practical Measures , 51 



Part II 



Key to known Larvae (and Pupae) of Syrphidae 52 



Synopses of Life History Studies 53 



I. Paragus bicolor. II. Paragus tibialis. III. Syrphus americanus; III. B. 



Syrphus sp. IV. Syrphus torvus. V. vSyrphus xanthostonms. VI. Didea 



fasciata. VII. Allograpta obliqua. VIII. Sphaerophoria cylindrica. IX. 



The-Cock's-Comb-Gall Syrphus-fly (undetermined). X. Eristalis aeneus. . . 

 Review of the Literature on the Biology and Metamorphoses of Syrphidae, 



arranged generically 62 



Part III 



Key to the Genera of vSyrphidae 74 



List of Ohio Species with keys to the Species of the various Genera which have 



been, or are likely to be, collected in the State 79 



Brief Bibliography 99 



