13 



PAGE 



EIGHTEENTH REPORT 



List of Descriptions V 



Letter of Transmittal VI 



General Record for 1891 and 1892 VII-XI 



Insect Injuries to Indian Corn, 1 1-165 



Introductory 3 



Classification of Injuries 



Injuries to the Seed in the Earth 7-51 



Injuries by Ants 9-12 



Solenopsis debilis 9 



Myrmica scabrinodis lobicomis 11 



Injuries by Beetles 12-16 



. Igonoderus pallipes ' 1- 



Aphodius granarius 14 



Clivina impressifrons IS 



Injuries by bootless Maggots 16-2] 



Anthomyia sew (The Seed-corn Maggot) 16 



Sciara sp. (The Black-headed Grass-maggot) 19 



Injuries by Six-legged Larvae 21-51 



Systena tceniata (The Pale-striped Flea-beetle) 21 



Ips fasciatus ( The Banded Ips) 23 



Wireworms 28-51 



Synopsis of Genera 31 



Cardiophorus sp 32 



Drasterius elegans 34 



[griotes mancus (The Wheat Wireworm) 36 



Agriotes pubescens 39 



Melanotus communis 39 



Melanotus fissilis 41 



Melanotus infaustus 4? 



Melanotus cribulosus (The Corn Wireworm) 42 



Asaphes decoloratus 45 



Natural Enemies 47 



Prevention and Remedy 4S 



Injuries to the Roots 52-165 



Injuries by Plant-lice and Mealy Bugs 55-108 



Aphis maidiradicis ( The Corn Root-aphis) 58-85 



Schisoneura panicola ( The Grass Root-louse) 85-93 



Trama erigeronensis 93-95 



Forda occidentalis, n. sp 95-97 



Tychea brevicornis, n. sp 97-98 



Geoica squamosa, n. gen. et sp 98-104 



Rhisobius ipicatus, n. sp. (The Woolly Grass Root-louse) .. 104-106 



Dactylopius sorghtellus ( The Sorghum Mealy Bug) 106-108 



Injuries "by White Grubs _ 109-145 



Lachnosterna and Cyclocephala (Common White-grubs) ... .109-144 



Allorhina nitida (The Green June Beetle) 144 



Prionus Grubs 146 



Injuries by Root-worms 146-165 



Diabrotica 12-punctata (The Southern Com Root-worm) .... 146-154 



Diabrotica longicornis (The Northern Corn Root-worm) .. ..154-165 



Explanation of Plate- 167-170 



NINETEENTH REPORT 



Letter of Transmittal 3 



Experiments for the Destruction of Chinch-bugs as they Emerge from 



Fields of Small Grain at Harvest 5-15 



On Contagious Disease in the Chinch>bug 16-176 



