THE LACHRYMAL GLAND 173 



long axes being parallel to the cirumference of the tubules. 

 Here is seen a more pronounced example of the statement that 

 the long axes of the nuclei of the outer layer are at right angles 

 to the long axes of the nuclei of the inner layer cells. The 

 cells of the outer layer are frequently so elongated that they 

 resemble connective tissue cells. The nuclei of both layers are 

 similar in staining characteristics. 



The connective tissue wall surrounding the epithelium \'aries 

 in amount depending upon the thickness of the septa in which 

 the ducts are situated. A well defined basal membrane upon 

 which the epithelial cells rest is plainly seen with Mallory's 

 stain. Practically all the elements described for this wall 

 under the caption of the primary ducts are seen in these walls — ■ 

 with a reduction in quantity, however. There is a marked 

 decrease of elastic fibres. It is only necessary to contrast the 

 smaller interlobular ducts with the larger primary ducts to 

 appreciate this statement. In the wall of the primary ducts 

 numerous elastic fibres are seen throughout the connective tissue 

 wall while in the smaller interlobular ducts the elastic fibres 

 occur sparsely or may not be seen. The accompanying arteries 

 and veins, however, show these deep staining fibres in their 

 walls and may be used for comparison. The decrease and dis- 

 appearance of the elastic fibres take place between the origin 

 of the primary ducts and the smaller interlobular ducts. The 

 quantity of elastic fibres present is proportional to the thickness 

 of the walls and septa in which the ducts are embedded. Where 

 the connective tissue wall is much reduced and the septum is 

 thin elastic fibres are only sparsely present or are not seen at all. 

 The walls are composed almost entirely of collagenic fibres as 

 revealed by Van Gieson's stain. Numerous cellular elements 

 are present which may be classed similar to those of the primar}- 

 ducts. 



Intralobular ducts. Intralobular duct;^ vary much in the size 

 of the lumina and the quantity of the surrounding connective 

 tissue. Some ducts appear greatly dilated with lumina 70m 

 in diameter. These dilated ducts are not frequently found and 

 are doubtless abnonnal. Many again are seen which correspond 



