264 D, D. CUNNINGHAM. 
tinct areas appear to be present in the body in this state; we 
have first a dense granular central portion constituting the sub- 
Fic. 12.—Ameeba in epithelioid state with dividing nucleolus x 1000. 
stance of the ridges and the thicker portions ; beyond this is a 
highly refractive area devoid of granules, and external to this 
again is a delicate tenuous layer of the protoplasm, often only 
distinguishable with difficulty from the surrounding medium. 
All the vital processes seem to be carried on in such cases with 
extreme slowness. The contractile vesicle dilates very gradu- 
ally and often only undergoes imperfect obliteration on contrac- : 
tion, or it may remain absent for prolonged and uncertain 
intervals. In other cases it seems to be rigidly fixed in full 
dilatation. In appearing it sometimes is developed from a 
single centre, in other cases several minor vesicles appear and 
fuse into one as they increase in size. Granules of nutritive 
matter are ingested and frequently accumulate in spherical 
masses within vacuolar spaces filled with fluid. In other cases, 
however, they are irregularly diffused. When in full activity, a 
constant succession of fluctuating vacuoles is present in the 
body-substance. In some cases, and apparently connected with 
or preparatory to the resolution of the body into a collection of 
sporoid reproductive bodies—as it only occurs where they have 
ceased to move and have become aggregated in sporangoid 
masses—the large Amozbz in place of showing at utmost two 
large nucleolar bodies as they normally do, contain from three 
to eight of smaller size (Pl XVIII, fig. 11). From the appear- 
ance and arrangement of these in different cases, there can 
be no doubt that the increased numbers are due to repeated 
binary division of the nucleoli originally present. 
The size of the Amuebe and nuclei varies so extremely in 
different cases and at different times that it is impossible to give 
any useful average measurements. ‘They very frequently, when 
in an irregularly rounded condition, measure from 15 to 25 win 
diameter, with nucleoli, which, when paired, have a diameter of 
8:5 u, and when in larger numbers measure only half as much or 
under. ; 
