The Bionomics of South African Insects. 289 



B. Historical 415 



C. The Demonstration by GuY A. K. Marshall that Precis 



simia is the Wet Phase of P. antilope 418 



D. The Habits of the two Seasonal Phases of the South 



African Species of the Genus Precis, and the Stations 

 they respectively occupy 420 



E. Evidence of Adaptation in the conspicuous undersides of 



the Wet-Season Phases almost equal to the proof of it 



in the cryptic Dry Phases 424 



F. The severity of the Stru(j(jle for Existence among Insects 



in the African Dry Season as compared with the Wet. 

 The relation of the Seasoned Changes in Precis to those 

 of other Butterflies 432 



G. The succession of the two Seasoned Phases of Precis 



sesainus in Nature 443 



H. The attempt to control the Phases of P. sesamus and 

 P. arcliesia by the artijicicd application of Moisture 

 and Heat to the earlier stages. Suggested lines of 



Experiment 450 



I. The Bearing of the Seasonal Phases of Precis upon the 



Science of Insect Systematics 458 



29. The Gregarious Instinct in Hybernation and Emi- 



gration OF Insects. (E. B. P.) 460 



30. Description and Discussion op Material bearing on 



Mimicry in South African Rhopalocera collected 

 BY Guy a. K. Marshall, and the Record of 

 Observations made by him. (E. B. P.) 466 



A. Black-and-White Amauris-like Group 466 



B. Limnas clirgsippus-like Groups 468 



C. Tlie Origin and Meaning of the Three Chief Forms of 



Limnas ehrgsippris 473 



D. A stiidy of Mimetic Forms may enable us to reconstr'nct 



the Lost Stages through uliich the Older Model has 

 passed 482 



E. Amauris echeria-like Group : marked Secondary Resem- 



blances bettveen the Forms mimicking echeria . . . 484 



F. The Origin of the black-marked ejolden-brown Triangle 



at the base of the Hind- Wing under-side in many 

 Ethiopian Butterflies 488 



G. Compound Group containing Representatives of edl the 



three previously elescribed. Species probedjlg entering 



tivo Group>s 490 



H. Groupjs of Synaposematic Acrazas captureel at the same 



Place and Time 492 



TRAKS. ENT. SOC. LOND. 1902. — PART III. (NOV.) 20 



