THE LACHRYMAL GLAND 193 



nation of this phenomenon is, as suggested by Bensley — ''the 

 granule substance has a primary difference of density due to 

 difference in water content or a change in dispersion grade of 

 the colloid." Certainly some granules retain the stains much 

 more tenaciously than do others. I have not observed these 

 extreme variations in the staining reaction of granules in other 

 glands such as the pancreas and submaxillary. 



The secretion granules of the lachrymal gland are not stained 

 in neutral red or in any other of the vital stains employed. 



I saw no free granules in the lumina of either the tubules or 

 the ducts. Frequently such appears to be the case however, 

 for one sees, especially in the intercalary duct, elongated groups 

 of granules which seem to be in the lumen. Careful study, 

 however, reveals the fact that these granules mark the proximal 

 end of the other cells which contribute to the formation of the 

 lumen. 



No cuticle, striated or otherwise, was observed in the epithelium. 



Discussion of granules 



■ Secretory changes in cells. Unfortunately the lachrymal gland 

 of the ox does not lend itself for experimental study of a stage 

 of rest, a stage of activity, and a stage of exhaustion. Studies 

 based upon microscopic changes in the cells as induced by rest 

 and stimulation must be accomplished in the more accessible 

 laboratory animals. My study of granules was based chiefly 

 on the methods of their conservation and their staining char- 

 acteristics. However, a sufficient number of glands was exam- 

 ined to gain some light upon the changes that do occur in the 

 normal secretory activity of the gland. According to the tissues 

 fixed in Bensley's sublimate alcohol bichromate solution and in 

 formalin bichromate solution supplemented by a study of fresh 

 tissues the secretory phases of the gland may be classified as 

 follows : 



A. A maximum granular stage in which most of the cells of 

 the tubules and intercalary ducts are filled with granules. The 

 majority of cells in the tubules belong to those described as type 



