DESCRIPTION OF PLATE IX.— (Frontispiece.) 



Represents the dorsal aspect of the fly's proboscis, mounted in balsam 

 ■without pressiu-e, magnified about 40 diameters, and it is intended to shew the 

 relations of the several parts. The lips are more inflated than is natural 

 during life, a result which cannot be avoided in preparations like that from 

 which the accompanying plate is taken. 



