254 



ANATOMY OF VERTEBRATES. 



collectively ? ciliary zone,' or ' corpus ciliare? fig. 198. Of these 

 folds, in Man, there are from sixty to seventy, about two lines in 

 length, but alternately a little longer and shorter. The free central 

 or internal border of the fold 

 sinks into the contiguous hya- 

 loid membrane, round the cir- 

 cumference of the crystalline 



198 



f »7 



Ciliary ligament and iris, cv' 



Ciliary zone, iris, and pupil, from within ; Human, inagn. 

 cvi". 



199 



lens, the anterior ends of the processes project into the posterior 

 chamber of the aqueous humour, touching the iris, and bounding 

 peripherally that chamber. The circular screen or curtain at- 

 tached at its periphery to the ciliary ligament, and interposed 



between the cornea and lens 

 is called the ' iris ; ' its aper- 

 ture is the ' pupil,' which is 

 nearly in the centre of the 

 disc, but a little toward the 

 nasal side. The anterior sur- 

 face of the iris, fig. 199, pre- 

 sents linear elevations, irre- 

 gular in size and number, 

 converging to a circular one 



about ¥ V tn °f an mcn f rom th° 

 margin of the pupil : from the 

 ' circle ' numerous minute strire 

 converge to the margin itself. 

 The anterior surface is the seat 

 of that variety of colour, to which, in common parlance, the colour 

 of the eye itself is attributed. The posterior surface of the iris is 

 covered by a thick layer of black pigment which when removed 

 exposes a number of lines converging from the ciliary folds to 



Anterior surface of iris. cv". 



