CONTENTS 



Vagc. 



Introduction 71 



Experiments 72 



General methods of experimentation 72 



Behavior of Limncrium validurti (Cresson) in confinement 73 



Limnerium validum as a parasite of Euproctis chrysorrhoa (Unnaeus) 73 



First experiment 74 



Second experiment 74 



Amcebocytosis as a protective reaction of the host 75 



Adaptation of parasite to host 76 



Further experiments with Euproctis chrysorrhaa 77 



Limnerium validum as a parasite oi Malacosoma americana (P'abricius) 78 



Results of experiments as determined bj^ dissection 78 



Emergence of adults of Limncrium from reproduction 79 



I^ength of the stages in the life history of Limncrium 80 



A possibly normal parasite of Malacosoma 80 



Limnerium validum as a parasite of Notolophus cmiiquus (Linnaeus) 81 



Limncrium validum as a parasite of Porthetria dispar (Linnaeus) 82 



Experiments with other hosts 83 



Notes on development and anatomy of the larva 83 



The egg 83 



The first-stage larva 84 



Description of the newly hatched larva 84 



Function of the tail appendage 85 



Appearance of older larva> 85 



Notes on the anatomy of the larva 86 



The second-stage larva 87 



The third-stage larva 87 



Description of the full-grown larva 87 



Feeding habits of the imprisoned larva 88 



Respiration of the larva in the third stage ' 89 



The cocoon 90 



Results of the dissections of Hyphantria during the fall of 1910 90 



General summary 91 



Bibliography 92 



III 



