319 



RESEARCHES ON THE INSECT METAMORPHOSIS. 



PART I. -ON THE STRUCTURE AND POST-EM BRYON IC DE- 

 VELOPMENT OF A CHALCID WASP, NASONtA. 



PART il.-ON THE PHYSIOLOGY AND INTERPRETATION OF 

 THE INSECT METAMORPHOSIS. 



By O. W. TiEGs, M.Sc, 

 Zoology Department, University of Adelaide. 



[Read October 19, 1922.] 



Plates XV. to XXX. 



Page 



Introduction ... ... ... ... ... ... ... ... 322 



Paut I. 

 On the StpvUcture and Post-embryonic Development op a 



Chalcid Wasp, Nasonia .. ... ... ... ••• 326 



A. The External Features 326 



General Remarks ... ... ... ... ... ... 326 



The Head and its Appendages... ... ... ... 329 



The Constitution of tie Head ... ... ... ... 334 



The (true) Thorax and its Appendages ... ... 337 



The Abdomen and its Appendages ... ... ... 341 



The Ovipositor ... ... ... ... ... 343 



The Penis 346 



B. The Integument (Histological Development) ... ... 348 



The General Body Integument ... ... ... 348 



Destruction of the Body Integument ... ... 349 



Metamorphosis of the Underlying Somatopleure ... 350 



Renovation of the Epidermis ... ... ... ... 350 



Formation of Body Sculpturings ... ... ... 351 



Formation of Bristles ... ... ... ... 352 



Formation of Pubescences ... ... ... ... 352 



The Phragmas ... ... ... ... .•• 353 



The Legs 354 



The Wings 357 



The Mouth Appendages ... ... ... ... 360 



The Ovipositor ... ... ... ... ... 362 



The Penis ... ... 364 



The Antennae ... ... ... .•• ... 364 



The Organs of Vision ... ... 369 



The Compound Eyes 369 



The Ocelli 384 



