192 NOTES AND COMMENTS [maech 1899 



lizard, which is death on rats. Mr. Ferguson's lecture contains some 

 interesting notes on these animals and on local superstitions attaching 

 to them. Travancore is to be congratulated on its gardens and 

 museum, and still more on having so capable a public servant as Mr. 

 Ferguson. 



The Transformations of an Earwig. 



In 1881 the late Prof. Westwood described, under the name Dyscritina 

 longisetosa, an insect from Ceylon, with the head and body of an 

 ordinary earwig, but with a pair of long jointed cercopods on the last 

 abdominal segment instead of the usual forceps. Entomologists have 

 long suspected that this curious insect would prove to be the immature 

 stage of an earwig ; this opinion has now received confirmation by the 

 researches of Mr. E. E. Green. In the latest part of the Transactions 

 of the Entomological Society, 1898, pp. 381-390, Mr. Green gives an 

 account of the development which he has traced, and Mr. M. Burr con- 

 tributes systematic notes on the two species of earwig which were 

 reared from two distinct forms of Dyscritina. They are referable to 

 the genus Diplatys, Serville. 



The most remarkable feature in the development of these insects is 

 the method of transformation of the long jointed cercopods into the 

 forceps. In one of the species examined the cercopods are much longer 

 than the insect's body, in the other somewhat shorter ; but in both the 

 basal segment of the cercopod is longer and stouter than the succeeding 

 segments. At the last moult but one, all except the basal segments 

 are completely shed ; Mr. Green believes that the insects actually bite 

 them off ! "Within the truncated cercopods the forceps of the adult can 

 be clearly seen, and these are revealed at the final moult. 



It is likely that other tropical earwigs will be found to undergo a 

 similar change, contrasting strongly with our European species, which 

 are hatched with simple tail-appendages already resembling the forceps 

 of the adult. The observations of Mr. Green afford valuable support 

 to the view that the forceps are modified cercopods, and indicate the 

 affinity of earwigs to the Thysanura and Orthoptera, in which orders 

 jointed tail-appendages are so characteristic a feature. 



