vi CONTENTS 



XX. The ways of butterflies .... 181 



XXI. Butterflies at night and at sea . . 187 



XXII. Some singular things about caterpillars . 194 



XXIII. Where did the butterflies common to the 



Old and the New World originate ? 206 



XXIV. Antigen Y ; or sexual diversity in butter- 



flies 216 



XXV. Lethargy in caterpillars .... 226 



XXVI. A BUDGET OF CURIOUS FACTS ABOUT CHRYSA- 



LIDS 232 



XXVII. DiGONEUTISM IN BUTTERFLIES .... 242 



XXVIII. Periodicity in the appearance of butter- 

 flies > . 253 



XXIX. Color preferences of butterflies, and the 



ORIGIN OF their COLOR .... 256 



XXX. The friends and associates of caterpillars 263 



XXXI. Butterflies of the past .... 267 



Index to names of insects . . . « . . 277 



