1 12 



and a fibrous mucosa; next is the muscular coat, composed 

 of an inner circular, and an outer longitudinal layer of 

 non-striped muscle (-ells; lastly an outer fibro-elastic 

 coat. Sketch under high power. 



(f) Mammary Gland. 



SiiijiU pieces tuken from tlie inaminary filand of a nnrsuiy: Ijitcli 

 were liardened in inerciiric cliloride, stained in Delatieid's lueina- 

 toxylin, enil)edded in parafiin, and sectioned. The sections were 

 fixe<l to cover "ilasses, connter-stained in eosin, dehydrated, and 

 cleared in oil of l)er(;aniot and xyloL Monnt on Balsam. 



Study first under low power. Observe the acini i)f the 

 gland united into small lobules by fibrous tissue. Under 

 high power it will be seen that the acini are limited by a 

 membrana propria, and lined ]>y a single layer of cubical or 

 polyhedral cells. In the protoplasm of these cells, fat 

 droplets, varying in size, are often seen. The nucleus is in 

 the outer ]iart of the cell. The lumen of the acinus is 

 quite large, and often contains granules, droplets of fat, and 

 fragments of epithelium. Sketch a number of acini under 

 high power. 



DRAWINGS FOR LESSON XXIY. 



Il 



