346 THE LIFE OF AN INSECT. 



Now each of these little spaces is filled by a beau- 

 tiful minute lens of the same shape set in it. 

 On making a perpendicular cut into the eye it has 

 been found to consist of various layers: the outer 

 layer is a hard clear membrane composed of a 

 multitude of six- sided facets, 

 each forming a more or less 

 ^distinct cone-shaped cylinder, 

 which runs towards the centre 

 of the eye, as seen in the cut. 

 Under this is a layer of coloured 

 matter, sometimes of a violet, 

 ' Eye or green, or even reddish hue, 

 which is pierced with as many holes as there 

 are facets. Beneath this there is a varnish of a 

 black colour, within which is a second layer of 

 coloured matter ; and in the space 

 between this last and the first co- 

 loured layer the delicate fibres of 

 the nerve of sight, or optic nerve, 

 run. These fibres then converge 

 together at the back of the eye 



Magmfled^ecUon of part j nt() a gi n gl e l ar g e HCrVC, which is 



connected with the insect's brain, and conveys 

 the impression of sight to that organ. 



