EXPLANATION OF THE PLATES. 199 



FIG. VI. Milk from the human female. 1, Milk of the 



first day ; 2, colostrum corpuscles ; 3, free oil globules ; 4, milk 

 on the sixteenth day after delivery from the same woman. 



PLATE XIX. 



CLUSTERED GLANDS, Continued. TUBULAR GLANDS. 



FIG. 1. Portion of dried and inflated lung, seen with a 

 magnifying power of 25 diameters. 



FIG. II. Pulmonary vesicles from a fresh lung. 1, Walls 

 of the vesicles ; 2, layer of epithelium lining the walls of the 

 vesicles. 



Fig. III. Pulmonary epithelium from a foetus at the third 

 month. 1, Cells in their normal relation ; 2, detached cells. 



FIG. IV. A sweat gland, seen under a magnifying power 

 of 165 diameters (from the palmar surface of the middle finger). 

 1, Excretory duct lined by its epithelium ; 2, nuclei of the epi- 

 thelium ; 3, commencement of the excretory duct ; 4, fibrous 

 stroma (connective) of the gland, showing numerous plasmatic 

 cells (5). 



FIG. V. Excretory duct of the same gland. 1, Its external 

 layer consisting of connecting tissue ; 2, its internal layer 

 structureless basement membrane ; 3, polygonal epithelium. 



FIG. VI. Same duct seen in transverse section. 1, 

 Wall of the duct; 2, its epithelium; 3, its cavity. 



FIG. VII. Transverse section of the excretory duct 

 of a ceruminous gland. 1, Its walls, showing plasmatic 

 cells ; 2, its contents; 3, young cells, such as line the walls of 

 the gland ; 4, cells a little more advanced in age. 



