Mr. J. O. Westwood on the Earwig. 157 



Ly a membranous ligament from within, may not be the true men- 

 turn rather than an integral portion of the head, in which case the 

 organ itself would form the labium ; but the point may be open to 

 controversy, and a careful examination of a species of Platypus while 

 in a recent state, with due regard to the trophi of other allied genera, 

 •would appear to form the safest guide to a correct conclusion in the 

 matter. 



The labial palpi in Platypus cylindrus are of equal thickness to 

 the base ; but in PI. insignis the basal joints are much the thickest, 

 and the terminal joints shorter in proportion. 



From all these various circumstances, and more especially from 

 the very marked peculiarity in the antennae, this insect appears to 

 deserve the rank of a distinct subgenus ; and at the suggestion of 

 Mr. Westwood, I would propose for it the name of Tesserocerus, as 

 not inapposite with reference to the curious formation of the an- 

 tennae. 



XXXIII. OntheEarwig. Bi/ J.O.WESTyrooD,F.E.S.,S^c. 



[Read October 6,1834.] 



It has been considered by some authors that those species of insects 

 which subsist upon plants which are not natives of this country 

 ought not to be regarded as indigenous although occurring in the 

 greatest plenty. This opinion needs however to be received with 

 much restriction, since if adopted in its full extent it would neces- 

 sarily lead to the supposition that so strict a connexion exists be- 

 tween the plant and the insect that the latter is not found to attack 

 any other plant. 



But any person at all acquainted with floriculture knows well 

 that many imported plants afford the most congenial food to our 

 strictly native insects ; for instance, the flowers of the dahlia * are 

 gnawed, almost as soon as they have burst the calyx, in a very un- 

 sightly manner, but it is to the snails that the greatest portion of the 

 damage must be laid. The earwig however has not an inconsiderable 

 share in the mischief, feeding upon the corollas by night, and hiding 

 itself between them by day. In fact these insects are great enemies 

 of the florist and fruiterer, feeding upon ripe and decayed fruits, and 



* In like manner I have observed that the hollyhock is attacked by Apion radiolum, 

 which undergoes its transformations in the stem, although its ordinary habitat is 

 Malva sylvestris. 



