556 



INSECTS AT HOME. 



been practised in the anatomy of other orders, the reader will 

 not find miicli difficulty in mastering the details of a Hetero- 

 pterous insect. The chief point lies in the beak, proboscis, or 

 promuscis, as it is called by some wi'iters. This instrument 

 is either three or four-jointed, the latter being the case 

 with the insect which is drawn in the illustration. This 



LXIII 



1. Seliirus dubius. 2. Head, jfront view ; a. Central lobe of face ; 6, Crown. 3. Head, 



under side ; a, Rostral channel, with the rostrum or beak in position. 4. Head, upper side ; 



a, Ocellus. 5. Head, profile ; a, Rostrum. G. Rostrum. 7. Antenna. 8. Leg; 



a. Fulcrum ; b. Femur or thigh ; c, Tibia ; d, Tarsus. 9. Elytra and wing ; a, Clavus 5 



6, Corium ; c, Elytron ; d, Membrane ; e. Wing. 



does not, however, bonstitute the whole of the apparatus, as it 

 is only a sheath for the real piercing instrument, and is, like 

 the mask of the dragon-fly larva, a development of the labium. 

 If this sheath be opened under a microscope it will be found to 

 contain four delictite sharply-pointed bristles, which, when 

 examined by the aid of the microscope, are seen to be the jaws 

 and maxillae of the insect modified into this singular form. In 



