CONVERSAZIONE OF THE CITY OF LONDON ENTOMOLOGICAL SOCIETY. 119 



The body, broad at the upper part, ball-shaped and pointed at the 

 apex, and the flat outspread thorax which touched the ground, all 

 showed it to be unquestionably a protected guest. By these means, in 

 spite of its large size, 15mm, long, and 6mm. broad, the beetle was 

 able to live amongst the stinging Atta, even should they show it but 

 scant affection. The extraordinary likeness which this beetle exhi- 

 bited in colouring and hairiness to the big-headed red-brown Atta was 

 evidently calculated to deceive the host. The colouring and glossiness 

 were intended to deceive its sight, and the hairiness its touch. In 

 the same manner as in the Atta, the glossiness of the head contrasts 

 strongly with the dull-coloured body, so with the beetle, the shiny 

 thorax contrasts with the rest of the body. As the ant possesses 

 medium-sized compound eyes, the elements in the Atta guest's outward 

 appearance which were calculated to deceive the host's sight are easily 

 understood. The purpose of this passive mimicry, however, was not 

 very clearly determined ; it may have been, according to the above 

 mentioned facts, a twofold one ; either to make the guest more agree- 

 able to its host, or to defend it more easily against its hostile attacks. 

 It was necessary, therefore, to find other characters to explain this 

 case. It had a fine yellowish golden growth of hair underneath the 

 bristly hair of the abdomen, which thickened into patches towards the 

 edges. Still more noticeable was the thick long yellowish hair on the 

 under jaw which was visible to the naked eye. There were also short 

 golden tufts of hair on the anterior margins of the seven last joints of 

 the antennae, and lastly a golden-yellow shiny spot on the base of the 

 upper-lip, which enclosed above and below a row of long bristles. These 

 facts was sufficient to convince us that we had here a case of genuine 

 intercourse, though of a lower degree. The result of all these a priori 

 considerations is as follows — it is certainly a true guest of Atta sexdans, 

 which is the only one of the genus of this shape and colour in that 

 country, it is also one of the protected guests, and probably is not only 

 tolerated because of its invulnerability, but also enjoys a low degree of 

 genuine intercourse on account of its tufts of yellow hairs. I was 

 thinking of describing it under the name of Attejus bardariottii, but 

 before doing so it was necessary to search the systematic literature 

 to find out if it was a new species or not. I generally find that the 

 tropical ant and termite guests which are sent to me are new species, 

 but in this case it was not so. In the Staphylinidae of the Biologia 

 Centrali Americana, by David Sharp, I found my Atta guest described 

 and figured under the name of Cordylapsis pilosa, F.{Smilax americanus, 

 Lap.). 



(To he continued.) 



Conversazione of the City of London Entomological Society. 



By W. J. KAYE, F.E.S. 



The conversazione held by the City of London Entomological and 

 Natural History Society, in the larger hall at the London Institution, on 

 April 24th, 1900, proved a complete success, and the exhibits were more 

 diversified and numerous than on the previous occasion three years ago. 

 The excellent musical programme arranged by one of the secretaries, Mr. 

 S. J. Bell, added largely to the success of the evening. British and 

 exotic lepidoptera came in for the largest share of the exhibits. In 



