STRUCTURAL CHANGES IN THE POISON GLAND. 



31 



(C*) Gland 10 Minutes after Injection of Pilocarpine. 



Sections showed the granules still present in a considerable number of 

 cells, but the latter were less numerous than in the unstimulated gland. The 

 number of granules in each cell was also less. The lumen of the tubules con- 

 tained an abundant granular mass. 



Experiment III. 



An animal (D) was injected with 0.1 grain of pilocarpine and, after an in- 

 terval of 24 hours, pieces of the gland were removed and fixed in Kopsch fluid. 

 Examination of the sections indicated that the gland had almost regained its 

 normal activitj'. Some of the lobules were apparently perfectlj^ normal, the 







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Fig. 13. — Two thin sections of intralobular tubules of a gland 24 hours after injection of pilocarpine. Some cells show 

 initial steps in granule formation (Zeiss oc. 4, obj. 3 mm., ap. 0.95). 



number of granule-containing cells being nearly if not quite as numerous as 

 in similar lobules of the normal gland. In other lobules the number of such 

 cells was much less and in many instances they contained only a few granules. 

 In many cells the granules were apparently in the process of formation, appear- 

 ing as minute particles at the intersections of the cytoplasmic network. 



Fig. 13 represents a section passing through two intralobular tubules. The 

 greater number of cells, it will be observed, are filled with a relatively dense 

 cytoplasm similar to that which in normal granule-containing cells forms a 

 basal layer (c/. fig. 10). In other cases the cytoplasm is more clearly alveolar. 

 In these cells granules are usually present, in some cases in early stages of 

 formation, in others almost fully formed. 



