268 ELEMENTARY PHYSIOLOGY. [XXVI. 



bundles of circular fibres, the circular muscle 

 of Miiller, inside the longitudinal fibres will 

 be seen; in many lower mammals this part 

 of the ciliary muscle is small or absent.) 



d. The pigment-layer of the retina continuing 

 forwards to form the uvea of the ciliary pro- 

 cesses and of the iris. Inside this is a simple 

 layer of columnar cells without pigment, this 

 is a continuation of the inner coat of the 

 retina. 



e. The canal of Schlemm at the junction of the 

 cornea and sclerotic. 



2. In sections of a cornea which has been hardened 

 in mercuric chloride, and stained (cp. also p. 251), 

 observe 



a. The anterior epithelium. In this note 



a. The external flattened nucleated cells. 



/3. The middle layers of roundish but ir- 

 regular cells. 



<y. The internal single layer of columnar 

 cells placed perpendicularly, cp. Lesson 

 xxiv. A. 



b. The body of the cornea. Note 



a. The narrow transparent zone immedi- 

 ately beneath the epithelium, the an- 

 terior basement membrane of Bowman. 



/3. The rows of connective-tissue corpuscles 

 seen in profile, with numerous branches 

 communicating not only with the ceils 



