DEGENERATION AND DEATH IN ENTAMG@BA RANARUM. 715 
digestion (cf. text-fig. B), yet as degeneration proceeds no 
more food is ingested, and that originally present is but slowly 
digested. A few undigested remains of food are often seen 
in the enucleate forms (see text-fig. H, 2), but these are 
often quite hyaline and free from all trace of cytoplasmic 
inclusions. 
How long these organisms are able to remain alive in this 
condition when inside their host, I am unable to say. I have 
observed them undergoing active, and apparently quite normal, 
movements for many hours under the microscope, before 
death finally supervened. There is no difficulty in making 
such observations on the living animals, for—with proper 
TExtT-FIG. D. 
Degeneration nuclei; in optical section. P. gi.= Pigment granules. 
f=) Py 5 t=) 
procedure—the structure can be observed in the living animal 
with as much precision as in a fixed and stained preparation. 
There is absolutely no evidence to show that the amcebee 
are capable of recovery after the processes of degeneration 
which I have just described have once set in. I should also 
point out that this kind of degeneration and death differs 
entirely from that which happens to an ordinary individual 
when removed from its host. It is also quite different from 
the simple degenerative changes which sometimes occur in 
hypertrophied animals which have been kept for some days 
in cultures of the feces (see 2, p. 249). 
On several occasions I have found degenerate nuclei of the 
type seen in text-fig. D, 1. In these the whole of the central 
