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CHAPTER XXV. 



ORDER XII. APHANIPTERA. 



THE order APHANIPTERA contains the family of Fleas 

 only insects which, as that name imports, are entirely 

 destitute of wings. 



There may seem little that is remarkable in this cir- 

 cumstance ; apterous species, and apterous individuals 

 of winged species, being found in all or nearly all other 

 orders. But of the Fleas, which are considered to form 

 an order by themselves, not a single species. British or 

 foreign, is known to develope wings. It is true that four 

 little scales supposed to represent these are found upon the 

 thoracic segments, and Naturalists have observed " some- 

 thing like elytra," and "vestiges of wings," but any- 

 thing which could be called wings has never been found. 



Indeed, it seems that the process of development in 

 the Flea is arrested before it comes to the wings, for it is 

 unlike nearly all other insects (except such as the im- 

 perfectly developed female of the Glowworm) in having 

 no distinct thorax. The body, from the head to the 

 tail, is composed of a series of rings or plates, not 

 soldered together in separate masses as those which form 

 the thorax and abdomen in other cases, and the insect 

 thus assumes rather the appearance of such a larva as 

 occurs in the families with imperfect transformations, than 

 that of a perfect insect. 



