Oec 142 



Occiput. — The back of tte head, around the com- 

 mencement of the colhim. (L. ob, and caput, 

 the head.) 



Ocelli. — Simple eyes, small extra eyes, usually 

 situated on the top of the head. The cuticle 

 covering the eye is thickened like a lens. Below 

 the lens there is a layer of transparent cells, 

 continuous with the adjacent epidermal cells. 

 (L. ocellus, a little eye.) 



Ocellate, Ocellated, Ocelloid.— Furnished with round 

 spots surrounded by a ring of lighter colour ; 

 resembling ocelli in appearance. (L., ocellus.) 



Ocellus. — An eye-like spot of colour, consisting of 

 annuli of different colours, enclosing a central 

 spot or pupil. (L. an eye.) 



Ochraceus. — Brownish-yellow in colour. (Gr. 

 ochra, from ochros, yellowish.) 



Octoon.^^The eighth segment in insects. (L. octo, 

 eight.) 



Oculi. — Compound eyes. They consist of a large 

 number (as many as several thousand) of simple 

 eyes, closely packed together in the form of 

 hexagons. The compound eye is, however, 

 peculiar, in that the ommatidia are very narrow 

 and elongate, and each one consists of only a 

 few retinal (6-8) and vitreous cells. (Boas.) 

 (L. oculus, an eye ; L. oculeus, full of eyes.) 



Oculi approximati.— Eyes closely set together. 

 (L. oculus, and a, and proximus, near.) 



