250 
Intestinal Protozoa in Termites 
in colour during life. Beneath the body wall is seen a zone of particularly 
coarse and deeply stainable granules. It is specially dense under the thick 
wall of the bell. This layer of granules lies beneath the body wall, and it is 
found in good preparations that they are embedded in a very thin layer of 
transparent and structureless substance lying immediately under the body 
wall. 
The nucleus is invariably situated in the median line and a little anterior 
to the middle point. It does not lie freely in the endoplasm, but has a special 
structure keeping it in connexion with the body wall. This interesting structure 
was called by Grassi the “cestello"’ or “little basket/’ and I propose to use 
the term “ corbule ” for it in this paper. The corbule has the following structure. 
In living as well as in stained preparations, a distinct zone of granules, identical 
with those distributed beneath the body wall, is seen on both sides of the 
nucleus, connecting its posterior surface with the wall of the bell. Careful 
study reveals the presence of a thin membranous structure resembling an 
inverted cone or a hemispherical bowl, with the granules on its internal 
surface; and it can be seen that the nucleus is situated at its bottom. At 
the edge of the bell the granules lining the membrane pass gradually over to 
the well-developed layer of similar granules under the body wall. In the 
peripheral part of this structure, the granules are distributed as deeply as 
under the wall of the bell; and the outline of the structure itself is so sharp 
on its external surface that the existence of a distinct membrane seems quite 
certain. Towards the nucleus, however, the membrane becomes gradually 
indistinct, and it is often quite obscure in the immediate vicinity of the 
nucleus. The granules are commonly distributed uniformly, both under the 
wall of the bell and on the membrane, but in some individuals a regular 
alternate arrangement of dense and thin bands of granules is noticeable 
(PI. X, fig. 4). The bands are usually of almost uniform width and are found, in 
well-developed cases, extending from the middle part of the bell to the 
vicinity of the nucleus. 
The shape of the corbule is more or less variable. Usually it assumes, in 
my organisms, the shape of a hemispherical bowl, with the nucleus situated 
just at its bottom; neither the membrane nor any trace of the granules being 
discernible behind the nucleus (PI. X, fig. 1). In some individuals, however, it 
assumes the shape of an inverted cone, touching the nucleus tangentially; and 
the membrane is then visible behind the nucleus, with granules attached to it, 
and sometimes appears fibrous (PI. X, figs. 2 and 3). In some other individuals 
the structure is indistinct in the vicinity of the nucleus, and an irregular 
mass of granules is seen around the latter. In my organisms still another 
structure, keeping the nucleus in connexion with another part of the body, 
is recognizable. This is a columnar mass of somewhat indistinct contour, ex¬ 
tending perpendicularly from the apex of the bell to the nucleus (PI. X, fig. 3). 
It apparently consists of the same kind of granules as those under the wall 
of the bell and on the corbule, but I am of the opinion that there is really 
