THYSANOPTEEA. 



CHAPTER I. 



Tfe little creatures which will be briefly described in :Les6 

 pages are now ascertained to belong to a separate order, 

 which has been named Thysanoptera, on account of the 

 curious structiu"e of their wings. This name is derived from 

 two Greek words — one signifying a tassel, and tlie other a 

 wing — and has been given to the insects of this order because 

 their wings are furnished on the edges with a frino-e of Ions: 

 hairs. These wings are long, narrow, and are not folded, but 

 lie flat along the back, and slightly crossed over each other. 

 There is no distinction between wings and elytra, and in most 

 of the species the hairy fringe is more than twice as wide as 

 the wing which it surrounds. In some species the wings are 

 long, but in some they are short, while in others they are 

 practically absent, being only represented by the undeveloped 

 rudiments. 



One of these insects, Phlceothrips coriacea, is shown in 

 Woodcut XXVII. Fig. 1 , and is a good example of the order. 

 As may be seen by the lino on its left side, it is a very tiny 

 insect, about tlie twelftJi or fourteenth of an inch in lengtli, 

 and yet it is larger than many of the same curious group. 

 Owing to their small size, it is not very easy to make out their 

 structure, but the reader should try, with the aid of the micro- 

 scope, to examine the head and the parts of the mouth, whicli 

 are very remarkable ; and, though formed of mandibles and 

 palpi, are united into a sort of conical sucker, which lies under 

 the breast when the insect is still. 



There is no difficulty in procuring specimens, as the insects 

 axe exceedingly plentiful — much too plentiful indeed — and 



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