TABLE OF CONTENTS TO REPORT II. 15 



REPORT II. 



[Submitted December 2, 1869; published March, 1870.] 

 Preface 



NOXIOUS INSECTS. 



Report of the Committee on Entomology of the State Horticultural 



Society 5 



Noxious insects less injurious in Missouri in 1869 than usual, 5 The Army 

 Worm and the Grain Plant-louse considerably injurious in Missouri iu 

 1869, 5 The Chinch Bug and the Codling Moth less injurious, 6 A 

 species of Tlirips destroying great numbers of the Curculio, 6 Eggs of 

 the Apple-tree Plant-louse destroyed by insect foes and birds, 6 Ac- 

 cording to Dr. Hull the "scab" in apples is caused by the Apple-tree 

 Plant-louse, 7 The Pickle Worm doing great damage during 1869, 7 - 

 Importance of preventing the introduction of injurious insects, 7 Cul- 

 tivation causes insects to multiply unduly, 8 More attention paid in 

 Europe to injurious insects than in this country, 8. 

 IMPORTED INSECTS AND NATIVE AMERICAN INSECTS 



The imported Currant-worm much more injurious than the native, 8 

 Other instances showing the greater destructiveness of imported insect 

 enemies than of their native representatives. 9 Almost all our worst 

 insect pests and pernicious weeds have been introduced from Europe, 

 10 Few American insects and plants have become naturalized in Eu- 

 rope, 11 The American faun a and flora not so highly improved and de- 

 veloped as in Europe, 12 Australian fauna still more " old-fashioned" 

 than America, 12 The parasites of injurious insects are not imported 

 with the insects themselves, 13 Government aid should be solicited to 

 exterminate recently imported injurious insects, 13 But little atten- 

 tion given so far by our Government to assist the study of economic 

 Entomology, 14 Danger of introducing the Oyster-shell Bark-louse into 

 Missouri, 15 Immunity of the Pacific States from many of our fruit 

 insects, 15. 

 The Chinch Bug 15 



It is the most injurious of all insects infesting grain, 16 Its past history, 

 17 ; it was known in South Carolina in Revolutionary times, 17 ; it was 

 injurious in Missouri as early as 1854, 17 ; noticed in Illinois in 1840, 



17 ; it was very injurious in Missouri in 1868, 17 ; but hardly noticed in 

 1869, 17 Probable reason why it was not noticed in Missouri in former 

 times, 18 Why it is not injurious in Massachusetts and New York, 18 

 Its natural history, 18 The pupa state in the different insect Orders, 



18 Time required fcr different insects to complete the cycle of develop- 

 ment, 19 The Chinch Bug is two-brooded in Missouri, 19 Its winter 

 quarters, 20 Its rapid multiplication, 20 Dr. Shinier's account of ita 

 nuptial flights, 21 It deposits the eggs underground on the roots of 

 the plant, 21 The egg, 22 Dimorphous forms of the Chinch Bug, 

 22 Its destructive powers, 22 Account of its appearance in immense 

 numbers, 23 Heading off the marching Bugs by a barrier of pine 

 boards, 23 Heavy rains destructive to the Chinch Bug, 24 Moisture 

 injurious to the egg, 24 The Chinch Bug is always worse in a dry 

 season than in a wet one, 24 Dr. Shimer's theory on epidemic disease 

 affecting the Chinch Bug, 25 Cannibal foes of the Chinch Bug, 25 ; 

 several species of Ladybirds, 25; the Weeping Lacewiug, 26; How the 



