DISSECTION OF THE HEAD AND NECK 383 



Where does the hyaloid artery (A. hyaloidea) run in the 

 embryo ? 



Ciliary Zonule (Zonula ciliaris [Zinni]). (See Figs. 179 and 180.) 

 How is this formed? What is its relation to the corpus vit- 

 reum and to the lens? What part of it is known as the " sus- 

 pensory ligament of the lens"? Study 



(a) Zonular fibres (fibrae zonulares). 



(b) Zonular spaces (spatia zonularia) (0. T. canal of Petit). 



The well-known saccular appearance of these spaces may be 

 easily produced if the point of a fine blow-pipe be inserted into 

 them and they be inflated with air. 



FIG. 185. 



Facies anterior.. _^B mk - Facies posterior 



Polus anterior-'""!!!;" """ T p olus posterior 



''Axis lentis 



Aequator lentiscT 



The terms used for the orientation of the lens. (After Toldt, Anat. Atlas, Wien, 1903, 3 Aufl., 



p. 900, Fig. 1363.) 



Crystalline Lens (Lens crystallina). 



Cut through the fibrae zonulares of the zonula ciliaris [Zinni] 

 and remove the lens. Examine the following : 



(a) Capsule of lens (capsula lentis). 



(b) Anterior pole of lens (polus anterior lentis}. 



(c) Posterior pole of lens (polus posterior lentis). 



(d) Anterior surface of lens (fades anterior lentis). 



(e) Posterior surface of lens (fades posterior lentis). 



(f) Axis of lens (axis lentis). 



(g) Equator of lens (aequator lentis) (0. T. circumference). 

 (h) Radii of lens (radii lentis). 



Now divide the anterior part of the capsula lentis with a 

 sharp knife and press the lens out through the opening. Study 

 the stained capsule as it floats in water. Press the substance of 

 the lens (substantia lentis) between the finger and thumb, and 



