THE LACHRYMAL GLAND 161 



can be considered as reticular connective tissue in the sense of 

 Mall, and is almost identical in appearance to the reticular 

 framework of the submaxillary gland as shown by Flint. Accord- 

 ing to the Fhnt, Spalteholz method (Technique II, 1) and a 

 modification of Mall's method (Technique III, 2) it was shown 

 that this basement membrane is not digested in pancreatin while 

 the parenchyma entirely disappears. Satisfactory specimens 

 for study may be made by these methods and then staining by 

 either Mall's or Mallory's method (figs. 4 a and 4 b). Van 

 Gieson's stain also may be used. The presence of this basement 

 membrane after prolonged digestion shows that elastic fibres 

 do not compose it. 



Plasma cells 



Numerous plasma cells are seen in both the interlobular and 

 intralobular tissue, principally around the ducts and between 

 the acini. These cells are typical in appearance — round, more 

 or less eccentric nuclei with peripheral arrangement of the chro- 

 matin, and fine basophilic granules in the protoplasm. These 

 cells are differently shaped — some spheroidal, others elongated 

 and irregular in outline. Sections stained in neutral safranin 

 show these cells very clearly. They may be found singly or in 

 clusters (fig. 5). 



Since Waldeyer ('75) first designated certain cells as plasma 

 cells and Unna ('92) described these cells as purely pathological 

 in the skin, followed by other observers who stated that they are 

 present in normal tissues, there have been numerous contributions 

 regarding plasma cells and their distribution in glands. Klein 

 ('79, '82) and Cajal ('96) describe them as being present in the 

 submaxillary gland of man. Zimmermann shows in the lachry- 

 mal gland of man ''Granulirte Zellen (Plasmazellen?) mit je 

 zwei stapchenformigen Centralkorpern innerhalb eines granula 

 freien Hofes." Plasma cells have been described also by loan- 

 novices ('99) in glands of the tongue, and by Maximow ('01) 

 in submaxillary and retrolingual of the dog. According to the 

 latter they are comparatively few in the submaxillary and 

 numerous in the retrolingual. Krause ('98) calls attention to 



