MOTIONS OF INSECTS. 353 



than those of most other Hgmenoptera, while those that 

 have fewer nervures are more slender. This, however, 

 does not hold good in all cases so that the dimensions 

 and cut of the wings, the strength of their nervures, and 

 the force of their muscles, must also be taken into con- 

 sideration. The wings of many of these insects when 

 expanded, are kept in the same plane by means of small 

 hooks (Hamuli) in the anterior margin of the under 

 wing, which lay hold of the posterior margin of the 

 upper a . Another peculiarity also distinguishes them. 

 Base covers (Tegulce), or small concavo-convex shields, 

 protect the base of the wings from injury b , or displace- 

 ment. 



The most powerful fliers in this order are the humble- 

 bees, which, like the dung-chafers (Geotrupes\ traverse 

 the air in segments of a circle, the arc of which is alter- 

 nately to right and left. The rapidity of their flight is 

 so great, that could it be calculated, it would be found, 

 the size of the creature considered, far to exceed that of 

 any bird. The aerial movements of the hive-bee are 

 more direct and leisurely. When leaving the hive for 

 an excursion, I have observed that as soon as they come 

 out they turn about as if to survey the entrance, and then 

 wheeling round in a circle, fly off. When they return 

 to the hive, they often fly from side to side, as if to ex- 

 amine before they alight. When swarming, the heads 

 of all are turned towards the group at the mouth of their 

 dwelling ; and upon rising into the air these little crea- 

 tures fly so thick in every direction, as to appear like a 

 kind of net- work with meshes of every angle. The queen 



a Kirby Mon. Ap. Angl. i. 96. 108. t. xiii./. 19. 

 b Ibid. 96. 107. t. v./. 8. dd. 

 VOL. IT. 2 A 



