Volume VI I L April, l8gS. Number I. 



JOURNAL 



OF 



MORPHOLOGY. 



A CONTRIBUTION TO INSECT EMBRYOLOGY. 



WILLIAM MORTON WHEELER. 



TABLE OF CONTENTS. 



Page 



Introduction 2 



I. The embryonic development of the Locustidas 3 



1. The oviposition of Xiphidiiun ensiferum, Scud. 3 



2. The formation of the Xiphidium embryo audits backward passage 



through the yolk 5 



(a) Description of surface changes beginning with the completed 



blastoderm 5 



(b) The indusiiun {prmoral organ) in section 12 



3. The develop7nent of the embryo from the time of its reaching the 



dorsal surface of the yolk to revolution 18 



4. Variations in the development of the indtisium 25 



5. The revolution of the embryo 27 



6. The stages intervening between revolution and hatching. 29 



7. The development of Orchelimtim vtilgare 35 



II. Gastrulation in the Orthoptera 3^ 



III. The indusium and its homologues in the Arthropoda 55 



IV. General consideration of the embryonic envelopes and revolution of 



the insect embryo 59 



1. The amotion and serosa 59 



2. The yolk ^+ 



3. Blastoki7tesis ^7 



4. The elimination of the embryonic envelopes 7^ 



