MR. TRIMEN ON MIMETIC ANALOGIES AMONG AFRICAN BUTTERFLIES. 1 ( .) ( .) 



them as he would species of other families, soon finds his collecting-box alive with itfl 

 struggling occupants. So flexible are the wings, that the insect generally succeeds in 



■ 



yithdrawing them from crossed fences of pins which form a complete barrier to any 



motion on the part of ordinary Butterflies; and however bent and distorted tlie wings 

 may become in such exertions, I have never known a fracture of nervures or membrane 

 to result, the organs resuming their natural position even after having been bent double 





for some hours. "While entomologizing in Natal, my Kafir collector used often to brin 

 me numerous examples of the commonest species in his box, and when engaged in tin 

 necessary work of rejection, I constantly found the limp-winged Dana/da and Acraidce, 

 as soon as they were released from the transfixing-pin, fly off with perfect ease and 



apparent nonchalance. 



It is not difficult to perceive how important, as a reserve means of defence, tin 

 unusual elasticity of structure may prove. That birds, and other eaters of insects, ina\ 

 occasionally capture a Butterfly of these malodorous tribes before discovering its distasteful 

 character is not an unreasonable supposition, especially in seasons when an exceptional 

 scarcity of some favourite food may prevail. In such a case it may be safely stated that 

 the chances are very greatly in favour of a Danais or an Acraa escaping, if not uholh 

 unhurt, yet without serious injury, after rough treatment that would have proved fatal 



to a harder but less elastic animal*. 



More extended observation is necessary to prove by positive evidence that persecution 

 of the Danaidcc and Acraida has almost wholly ceased, although, negatively, the v> it ncs 

 borne by their abundance is very strongly in favour of this view. Some check upon 

 their inordinate increase must, of course, exist; and this is probably to be found in the 

 Ichneumon flies attached to the various species, the females of which are not likely to 

 be deterred by any odour from depositing their ova in the lams. Mr. Bates has re- 

 corded that the Heliconide Vanaidet, when at rest on leaves, did not "appear to be 

 molested by lizards or predaceous flies of the family Asilid*. which were very often seen 

 pouncing on Butterflies of other families." A well-known naturalist has quoted (in the 

 Westminster and Foreign Quarterly Review for July 1867, Article 1) an observation 

 by Mr. Belt, that a pair of Puff-birds, watched by him in Brazil, during half-an-honr 

 caught and brought to their nest various butterflies to feed their young, bu entirely 

 avoided the slow-flying Eeliconidce, which were about the spot in great numbers,. I 



* 



markedly 



wM<*. It is remarkable that the three 



Moths in which I have found this peculiarity most developed 

 /omosa— all have a strong and offensive odour, emit drops c 

 coloured, and abundant species. 



viz 



and 



and 



Mr 



Heli 



in recognizing all the so 



Heliconius and 





t It is not uncommon to hear doubt expressed as to w 



C<r 



case just mentioned is of importance. I have noticed d» j ^^ ^ ^ ^ rf 



b*r it to be disputed that the Goatsuckers eat ^T^TSTu -rveUous indeed if they ne g lect,i th, 

 insectivorous birds in all (and especially in tropical) countries, it won 



forge supply of food afforded by the gener 



defenceless 



3 z2 



