CILIARY MUSCLE. 305 



In meridianal sections the ciliary muscle exhibits the form of 

 a rectangular triangle, the shortest side of which is turned 

 forwards, and forms a right angle with the outer side. The 

 thickness of the muscle is about 0*8 of a millimeter. 



The greater part of the muscle is composed of meridianally 

 running fasciculi (fig. 362, a), forming a compact mass, which 

 constitutes the thick external portion, and makes up its larger 

 third. 



The deeper-lying fasciculi (6), which, like the preceding, 

 arise at the anterior external angle of the muscle, run diverg- 

 iiigly in a radiating manner to the inner side of the triangle. 

 In this course the radiating fasciculi frequently anastomose 

 with one another ; after they have reached the inner side they 

 become circular, and thus form a thick circular web along the 

 whole internal muscular surface (c). 



Moreover, the anterior side, and, to a certain extent, the 

 internal anterior angle of the ciliary muscle, include tolerably 

 thick fasciculi of circular fibres, the so-called circular or 

 annular muscle of Muller (d). The posterior fasciculi are 

 formed of those longitudinal fibres which have changed their 

 direction, the anterior represent a completely independent 

 muscle. 



All the meridianal and radiating fasciculi arise from the 

 anterior external angle of the muscle, and they are continuous 

 with a dense flattened expansion of connective tissue which 

 forms its annular tendon (e). This is directed forwards, lies on 

 the inner side of the canal of Schlemm, and is ultimately 

 itself continuous with the tissue of the cornea. 



That meridianal portion of the muscle which is in imme- 

 diate contact with the sclerotic consists anteriorly of regularly 

 arranged parallel laminae. In proportion, however, as we pass 

 farther backwards, this regularity of disposition disappears, so 

 that at a distance of three millimeters from the origin of the 

 muscle the fasciculi separating and anastomosing with one 

 another, form a series of loops, with their convexities turned 

 backwards, in which a part of the muscle terminates. The 

 other portion of the meridianally running fibrils preserves its 

 primary direction, and may be followed to a distance of from 

 five to six millimeters from the origin of the muscle, in the 



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