THE ANATOMY OF THE LARVA 



55 



transparent cjdinder. Indeed, to complete the development 

 of the eye of the imago no great alteration of the deeper 

 parts is required, but only the modification of the trans- 

 parent superficial layer of the eye into the beautiful system 

 of miniature dioptric systems, one for each end-rod, which 

 forms the most striking characteristic of the facetted com- 



FiG. 15. — To Illustrate the Anatomy op the Eye of the Larva. 



a, Radial section through anterior part of the head of the larva of Ciilex 

 pipiens, cutting through both eyes and the optic ganglia ; b, semi-diagram- 

 matic representation of three of the visual elements of the above more highly 

 magnified ; c, portion of tangential section of the outer layer of the pigmented 

 portion of the eye. 



pound eye. I have gone into somewhat more detail than 

 usual in this point, because I have nowhere met with any 

 account of the visual organs of these larva? which appears 

 to be based on actual observation of the family, most 

 authors being apparently content to assume that their eyes 

 must needs resemble the visual apparatus of other and 

 often very distant groups of invertebrata. It is clear that 



