682 Proceedings of Royal Society of Edinburgh. [sess. 
matin, arranged in karyosomes united by threads. Lanthanin 
granules are still abundant, of small size, but do not produce 
clouding ’ they stain of a lilac colour, tempered with grey. The 
nucleoli are mostly small, but a few large ones are seen in process 
of extrusion, and mitosis has again become visible. 
Nine hours after food. — (Fig. 11, coloured plate.) — The lumen 
is now very small owing to the cells almost filling it up. They 
are crowded with medium-sized zymogen granules, a few being 
larger. The cytoplasm stains pale blue, and appears only as a fine 
network between the granules. The nuclei, however, have again 
diminished somewhat in size to 10 x 12 ’57 g, which is almost the 
size they were to begin with. Their chromatin is abundant and 
blue in colour, and the lanthanin granules large and of a pale blue 
tint. Many cells are in process of mitotic division. 
We may now say that the cells have completed the cycle of 
their changes due to secretion. They appear to secrete for about 
three to four hours, and then to require about the same time to 
recuperate ; but the worm is still in the stomach at this period, and 
not completely digested. 
Thirteen hours after food . — -Lumen very wide and cells much 
shrunken, being almost reduced to thin strips lining the gland 
walls ; they contain only a few scattered zymogen granules situated 
mostly near the free ends of the cells. The cytoplasm is pale 
blue-grey and in small amount. The nuclei have a shrivelled and 
pale appearance, measuring only 8T x 10'2 g. Their chromatin 
has a pale spread-out look and watery-blue tint. The lanthanin 
granules are very scanty and of a pale blue colour. The nucleoli 
are small as a rule, and some are in process of extrusion. Mitosis 
is quite absent. 
Therefore, after recovering from their first exhaustion, the cells 
again commenced to secrete, and have now again reached a stage 
bordering on complete exhaustion. 
Fifteen hours after food. — (Photo. 7.)— Lumen again smaller 
owing to increase in size of cells, which contain a few more 
granules of large size. The nuclei are still small and wrinkled, 
measuring 8’2 x 12‘55 /x. They contain a moderate amount of 
chromatin, which has a spread-out, watery look. Lanthanin 
granules are fairly numerous and of a dark-grey slate colour. The 
