BLADDER. 89 



EXAMINATION (L). Note the (i) external fibrous coat of connective tissue; the (2) 

 middle or muscular coat, consisting of non-striped muscle arranged in two layers (a) an 

 external circular, and () an inner longitudinal, with the muscle-cells composing it cut 

 transversely ; and (3) the internal or mucous coat lined by stratified transitional epithelium. 

 (H). Study each of these coats, but note the transitional epithelium (p. 12) ; the upper cells 

 are polyhedral, and below them is a layer of pear-shaped, or club-shaped, cells. 



THE BLADDER. 



PREPARATION. Prepare this exactly in the same way as the ureter. Use the bladder of 

 a cat or dog. It must be cut into several pieces after being distended for two days. Make 

 vertical sections, and stain them with logwood, and mount in Farrant's solution. 



It has practically the same structure as the ureter. Outside is the (i) serous coat ; (2) the 

 muscular coat, with its fibres arranged in three directions ; (3) the submucous coat ; (4) the 

 mucous coat lined with stratified transitional epithelium. 



The bladder of the frog has already been alluded to (p. 36). 



The nerve-ganglia of the bladder and ureters are best studied by the lemon-juice and gold 

 method (p. xlv). 



N 



