344 PROCEEDINGS OF THE ACADEMY OF [May, 



which leads to the intestine, where they may lodge for a time and 

 temporarily block the passage. In other cases still the globules 

 only seem to be set free ; while the small zxjmogen granules seldom 

 come near the discharging end. The nuclei are not lost, nor is any 

 part of the cytoplasm below them,-^ 



After complete discharge the cells diminish rapidly in height 

 until they are quite flat. Even at this size they are easily to be 

 distinguished from young cells, which may as yet be no taller than 

 they, by the absence of small zymogen granules about the nucleus, 

 by the shape of the globules or globular spaces, and by a thickening 

 of the free edge (when this is not lost). The last two effects are 

 caused by a retraction, as if the cells were elastic. When dis- 

 charged the spaces occupied by many of the globules are obliterated, 

 and a thickening or moving together at the free edge occurs, form- 

 ing a layer which always stains densely (fig. 21) (this is the thick- 

 ening just mentioned). Those globules Avhicli are not discharged 

 suffer a change of form by compression, so that they are always 

 laterally elongated. I have not so far been able to follow the fate 

 of the discharging cells further than this, or to obtain further evi- 

 dence that they are completely destroyed and replaced by new cells. 



It will be observed from the table that discharging cells may 

 occur at any interval after a single meal up to 124 hours (No. 44), 

 although there is a marked decrease in the number after forty- 

 eight hours, and iu some cases hardly any are to be found at ninety 

 hours (Nos. 40, 41, 42). 



In a single case (41) some of the young cells seem to be dis- 

 charging a fluid substance ; but as the fixation is one which does not 

 always preserve the zymogen, and it has not been confirmed by any 

 perfectly trustworthy fixation, no account has been taken of it here. 



By whatever process the discharge takes place — fragmentation, 

 dissolution, or mere evacuation — in every case there issues the fluid 

 whose precipitate gives the characteristic coagulum. Fig. 20 shows 

 some of the globules maintaining their identity for a time, but 

 sooner or later dissolving. They are not the only source of the 

 fluid, for, as in fig. 22, which contains a very abundant interalveolar 

 substance, this as wtll as the alveoles of the cells contx'ibute to its 

 formation. As we have already observed, small zymogen granules, 



^' In one or two cases of excessive feeding, where tlie cells become 

 enormously gorged with a substance which stains blue in Biondi-Hei- 

 denhain, after Zenker and sublimate, tlie nuclei may be displaced and 

 lost in broken-off fragments (Nos. 14 and 46, table). 



