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Note ox a Stridulating Organ in a South African Ant. 



Streblogiiathus JEthwpiciis. 



By R. T. Lewis, F.R.M.S. 



( Read April 17th, 1896.) 



Plate XII. 



About three years ago I received from a correspondent in 

 Natal a black ant of large size, which was said to be capable of 

 squeaking when captured or otherwise irritated, and I was 

 asked to examine it under the microscope with a view to ascer- 

 tain if there was anything in the structure of the insect which 

 rendered this possible. The specimen was strongly curled up 

 and extremely hard and dry, and such examination as I then 

 gave it failed to disclose any competent stridulating organ, but 

 my attention was attracted by a curious pectenated spine or 

 comb upon the apex of the tibia of the 2nd and 3rd pairs of 

 legs in addition to the usual brushlike arrangement found in a 

 similar position on the 1st pair of legs and obviously used for 

 cleaning the antennae (Figs. 1, 2, 3). The use of these addi- 

 tional combs was not apparent, as the insect was but sparsely 

 covered with hairs, but as no complementary structure could be 

 found within reach, which by friction on the combs was capable 

 of producing the sound referred to, it was assumed that these, 

 at least, were not the organs concerned in its production. They 

 were, however, sufficiently curious and interesting in themselves 

 to warrant some description, and members now present will no 

 doubt recollect that I exhibited them under the binocular 

 microscope at one of the soirees of the Club held at the Free- 

 masons' Hall. 



On referring the question back to my friend I learned from 

 him that he had not himself heard the ant make any noise, but 

 was told by the natives that it did so, and he promised to verify 

 the matter at the first opportunity which presented itself. Last 



