INDEX TO PLATES. 



Pl. I. FaONTISPIBCl!. 



Pl. II page 8 



Fig. 1. Young; Worm escaping from pupa-case. 



Fig. 2. Eartliworm, showing hoois and swelled rings. 



Fig. 3. Anterior rings of Worm, witli lip, hooks, and 



respiratory apertures. — From Burmdster. 

 Fig. 4. Transverse section of Worm. — From ditto. 



Pl. in. Diagram showing the anatomy of Musca vomitoria 26 



Pl. IV 34 



Fig. 1. Head of House-fly, magnified 20 diameters : 

 a, a, feelers ; b, h, compound eyes ; c, proboscis. 

 Fig. 2. Magnified portion of detached cornea. 

 Fig. 3. Section of part of compound eye. 

 Fig. 4. Five ocelli, highly magnified. 



Pl. V. Proboscis of House-fly 43 



Fig. 1. Proboscis entire, showing lancets, &c. 



Fig. 2. Magnified ribs. 



Fig. 3. Magnified section of ribs. 



Pl. VI 51 



Fig. 1. Section of Fly, showing nervous system, &c. . 



a, wing; h, nervous system. 

 Fig. 2. Antenna of Fly. 

 Fig. 2 a. Sensory depressions and closed sacs on the 



same, highly magnified. 



