CONTENTS. 
Page. 
Introduction 9 
History 10 
Origin and distribution 12 
Food plants 13 
Character of injury and destructiveness 14 
Beetles related to the grape root- worm beetle 15 
Beetles frequently mistaken for the grape root- worm beetle 16 
Description 19 
The egg 19 
The larva 19 
The pupa 20 
The adult or beetle 21 
Seasonal history 22 
The adult or beetle 22 
The process and time of emergence 22 
Variation in the time of emergence 25 
Feeding before and after egg deposition 25 
Mating and its bearing upon egg deposition 28 
Process of egg deposition 28 
Variation in the number of eggs per cluster 29 
Number of separate ovipositions by individual females 29 
Number of eggs deposited by individual female beetles 30 
The oviposition period for the season of 1909 31 
Longevity of male and female beetles 32 
The egg : 33 
Incubation period of the egg 33 
The larva 35 
Vitality of the newly hatched larva 35 
Feeding and development of the larva before wintering 35 
Wintering of the larva in an earthen cell 36 
Spring feeding of the larva 37 
Time and making of the pupal -cell 37 
The post-larval stage 38 
The pupa 39 
The process of pupation 39 
Position of the pupa in the cell 39 
Time of pupation in the field and in breeding cages 39 
Duration of the pupal period 10 
Life cycle of the grape root-worm as determined by rearing 40 
Seasonal variations in the life history of the grape root-worm 41 
Rearing and experimental methods 44 
Summary of life-history studies of the grape root -worm 50 
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