344 



INSECT TRANSFORMATIONS. 



pared for swarming immediately, if there be a necessity 

 for it, or that the young queen may be in a 'condition 

 to drive out her royal mother and take her place if there 

 be occasion.'* 



It does not appear, however, that Swammerdam 

 proved by dissection the simultaneous existence of 

 air and blood vessels in the wings, but merely infers 

 this, as Reaumur afterwards did, from the phenomena. 

 But Jurine has since actually demonstrated that every 

 vein (nervure} of a wing contains an air-tube, which 

 originates in the windpipe,, and follows in a serpentine 

 form, without filling, every branchlet of the nervures. 

 Those who have not paid attention to this curious sub- 

 ject have little conception of the great diversity of forms 

 which are exhibited by the branchings of these nervures, 

 . not only in different orders, but even in different spe- 

 cies of insects. They differ, indeed, as much in this 

 respect as the leaves of plants do in their mode ot 

 veining. 



Wings of insects : or, wing of a beetle ; 6, wing of an earwig; 

 f, wing of a saw-fly 5 <7, wing of a crane-fly ; e, wing of a com 

 nion fly (Musca) ; /, wing of a midge (Psychoda). 



* Swammerdam, i, 187. 



