CONTENTS 



PAGE. 



Acknowledgments 3 



Biological Studies 5 



I. The life history of the corn-field ant, Lasins niger var. americanus Emery 5 



Methods 5 



Nuptial flights 5 



Founding of the colony 7 



Hibernation 24 



Summary 28 



Additional notes 29 



II. Experiments on the trail formation and orientation of the common house 



ant, Monomor'mm pharaouis L 31 



Additional notes 40 



Conclusions 41 



Embryological Studies 42 



Studies on the embryology of Camponottis herctileanus var. fernigiuetis 



Fabr. and Mynnica scabriiiodis var. sabuleti Meinert 42 



Methods 42 



The egg 43 



Formation of the blastoderm 47 



The development of the external form 56 



The development of the external form of the embryo of Myrmica. ... 59 



Literature cited 64 



Explanation of plates 69 



Vita 4 



