THE NEWTS STOMACH DURING DIGESTION 4O9 



The nucleoli are multiple and not surrounded by a ring of chromatin, 

 they vary in size from minute dots not larger than lanthanin granules to 

 bodies measuring 2,7 X i,s a. 



In shape some are rounded, others irregularly oval, they acquire a ve- 

 nous red tint with eosine and are therefore probably alkaline in nature, but 

 not so strongly so as the zymogen granules. The larger ones often présent 

 a central pale area or vacuole, this however is by no means constant. In 

 number the nucleoli vary considerably, there may be a îew tiny ones or 

 2 or 3 very large ones and some small ones in the same nucleus. Whether 

 the tiny particles of matter which stain like nucleoli are really to be regar- 

 ded as true nucleoli is difficult to décide, though I believe that they really are 

 nucleoli in process of formation. Unfortunately in this animal the absence 

 of a chromatin ring round even the largest nucleoli prevents one from dis- 

 tinguishing absolutely between true nucleoli and other bodies having a si- 

 milar reaction to dyes. Nevertheless I hâve very little doubt as to their 

 nucleolar nature. 



Hère and there it is possible to see one of the larger nucleoli in process 

 of passing through the nuclear wall into the protoplasm, where it may re- 

 main for a time, but eventually breaks down and disappears. There is no 

 évidence that such extruded nucleoli become converted directly into zymo- 

 gen granules as maintained by Ogata -' and later by ver Eecke ' in the 

 case of the pancréas, etc. 



20 Hours afterfood. — Plate I, fig. 2, and Plate III, fig. 2. 



In this animal, when the stomach was opened, the worm was found 

 partly digested and surrounded by a quantity of mucous like material. 



The oxyntic cells are small, in some cases almost iiattened and the 

 gland lumen is correspondingly large and stellate. The zymogen granules 

 have nearly disappeared from the protoplasm, those remaining being of 

 large size frequently measuring 2,16 .j. in diameter, with an average of 

 1,6 1^-. They are situated mostly near the free ends of the cells, leaving the 

 base and sides cle'ar. This gives rise to an appearance of two ill defined 

 zones in the cells; the one basai containing the nucleus, and other apical 

 containing the granules. Only a few cells however show this division into 

 zones, by far the greater number présent a few granules scattered throughout 

 the protoplasm. No zymogen granules are présent in the lumen, from which 

 it may be concluded that the granules dissolve in the protoplasm before the 



