92 A NATURALIST IN THE TRANSVAAL. 



showy it was resting in some numbers on the still 

 leafless branches of a solitary acacia on the bare veld. 

 Being far beyond our reach we threw large pieces of 

 quartzite against the branches, and the concussion, as 

 a rule, brought the insects to the ground, when they 

 were secured before they could take wing. This species 

 was always found on the branches of an acacia. Beetles 

 are, however, difficult to obtain ; they are plentiful for 

 a short time at the commencement of the rains, then 

 become scarcer as the summer season advances, and are 

 almost totally absent during the long dry season. 

 Although the hedges were a mass of roses constantly in 

 bloom during the summer, I w 7 as surprised to see how 

 little they were visited by floral beetles. Certainly 

 myriads of the Cetoniid Pachnoda flaviveiitris could 

 generally be seen, and also the large Cantharid Mylabris 

 ophthalmica, but the majority of all these flower-visiting 

 Coleoptera confined themselves to the small and obscure 

 bloom found on the veld. A new tree would burst into 

 bloom, its flowers lasting but a short time, during which 

 frequently a species of the Cetoniidse not hitherto seen 

 would visit in quantity this fugitive blossom and again 

 quickly disappear with it. 



From lono- observation in the field and of the contents 



^j 



in my cabinets at home, I had become convinced of the 

 phenomena and the truth of the theory of mimicry* in 

 the insect world, by which under the law of natural selec- 

 tion edible species showing any resemblance to inedible 

 ones, have gradually been preserved by the protection 

 thus afforded, and the same selective process going on 

 among their progeny for long periods of time has re- 

 sulted in those wonderful resemblances which we now 

 find among distinct orders of insects. So strongly was 

 this always in my mind that I frequently was stung by 

 real Hymenoptera, when I expected too much and 

 thought I might be handling an imitator. But the 

 tables were quite turned when I first captured a female 

 of the longicorn Amphidcsmus analis, which on a leaf 

 has a surprising resemblance to a female of the genus 



* Long since enunciated and proved by my friend Mr. H. W. Bates. 



