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Notes and Remarks on South Australian 

 Rhopalocera, 



By J. G. O. Tepper, F.L.S. 



[Read October 17, LS93.] 



Ill part 1 of vol. XVII. of the Transactions of this Society a 

 paper on the South Australian Rhopalocera is published by Mr. 

 O. B. Lower, apparently intended to be a summary of what is 

 known of the subject, frequent references being made to a pre- 

 vious paper published by me. As I cannot agree with many of 

 his statements, I beg to record my views of the contested points 

 in the order in which they occur in Mr. Lower's paper. 



" It is usually considered, I believe, that the scarcity (?) of 

 Rhopalocera in this colony is due to the great dryness during the 

 season of flight. Also the severe droughts we are subjected to, 

 ike. But my honest conviction is that the scarcity is due to the 

 want of systematic collecting" (p. 1). 



That the scarcity is real is shown by the fact that in the 

 smaller area of Victoria 31 species of butterflies are recorded in 

 the first part of the recently published " Victorian Butterflies," 

 while of the corresponding families Mr. Lower only enumerates 

 13 species in South Australia. That this scarcity is due to 

 physical causes is not only proved by the concurrence of all 

 previous collectors (Messrs. Angas, Behr, Bathurst, Jung, 

 Odewahn, Schulz, Waterhouse, Wilson Brothers, Mrs. Kraiisler, 

 (fee, beside me and my brother), but also by the corresponding 

 scarcity of the moisture-loving ferns and mosses. The causes 

 operate not only "during the season of flight," but chiefly upon 

 the critical stages of larval and pupal life. Scarcity or abundance 

 in the abstract is determined by the proportion of the number 

 of species and individuals to a given area and time. It depends, 

 partly upon the extremes of temperature (not the mean) which 

 the insects or their food-plants are capable of resisting, partly 

 upon absence or abundance of their enemies, where there are no 

 formidable barriers of a physical nature to free intercourse be- 

 tween adjacent regions. The occasional capture of solitary 

 specimens by zealous collectors only proves that the immigrants 

 have not been able to eflect a footing, or only a very tem- 

 porary one. Such sporadic wanderers occur even in England 

 and other old countries. Personal conviction is not evidence 

 unless supported by many years of experience in the field, and 



