318 THE NATURALIST IN NICARAGUA. [Ch. XVII. 



is wanting, when it resembles C. basalts. Professor 

 Westwood has also pointed out to me that the resem- 

 blance to the beetle is still further increased in the moth 

 by raised lines of scales running lengthwise down the 

 thorax. 



The phosphorescent species of Lampyridae, the fireflies, 

 so numerous in tropical America, are equally distasteful, 

 and are also much mimicked by other insects. I found 

 different species of cockroaches so much like thejn in 

 shape and colour that they could not be distinguished 

 without examination. These cockroaches, instead of 

 hiding in crevices and under logs like their brethren, rest 

 during the day exposed on the surface of leaves, in the 

 same manner as the fireflies they mimic. 



Protective resemblances amongst insects are so nume- 

 rous and wide-spread, and they have been so ably 

 described by Bates and Wallace, that I shall only 

 mention a few of the most noticeable examples that 

 came under my attention, and which have not been 

 described by other authors. Amongst these was the 

 striking resemblance between some beetles belonging to 

 the Mordellidse. These, in their normal form, are 

 curious wedge-shaped beetles, which are common on 

 flowers, and leap like fleas. In some of the Nicaraguan 

 species the body is lengthened, and the thorax and elytra 

 coloured, so as to resemble wasps and flies. In the 

 Mordellidse the head is small, and nearly concealed 

 beneath the large thorax ; and in the mimetic forms the 

 latter is coloured so as to resemble the large head and 

 eyes of the wasp or fly imitated. The species that 

 resembles a wasp moves its antenna} restlessly, like the 

 latter insect. 



