I have again to thank Miss Frances Rodwell for the invaluable assistance which she has given me in the work of translation and in the less interesting and more tedious department of research.

ALEXANDER TEIXEIRA DE MATTOS.

Chelsea, 1914.

Contents

[ TRANSLATOR'S NOTE. ]
[ CHAPTER 1. THE MASON-BEES. ] [ CHAPTER 2. EXPERIMENTS. ] [ CHAPTER 3. EXCHANGING THE NESTS. ] [ CHAPTER 4. MORE ENQUIRIES INTO MASON-BEES. ] [ CHAPTER 5. THE STORY OF MY CATS. ] [ CHAPTER 6. THE RED ANTS. ] [ CHAPTER 7. SOME REFLECTIONS UPON INSECT PSYCHOLOGY. ] [ CHAPTER 8. PARASITES. ] [ CHAPTER 9. THE THEORY OF PARASITISM. ] [ CHAPTER 10. THE TRIBULATIONS OF THE MASON-BEE. ] [ CHAPTER 11. THE LEUCOPSES. ]