262 
Intestinal Protozoa in Termites 
Differential staining of the several parts is not easy, and stained preparations 
are not so suitable for studying the structure of the head. The principal 
parts of the axial column are a circumferential wall or rind of a tubular form, 
and a central cone, or core, fixed within it. The tubular rind is of a nearly 
uniform thickness, measuring 1-5-2/a; and circular openings, measuring 4 7 5/x 
in diameter, are found at both its ends. The conical core is widest at the 
anterior end, fitting into the upper opening of the tubular rind and gradually 
decreasing in thickness posteriorly so that it resembles an inverted cone, 
having the greater part of its surface separated from the tubular rind. The 
conical core itself is not composed of a single substance, but a body assuming 
the shape of an inverted cone or hemi-ellipsoid is found embedded in its 
anterior or basal portion. The main portion of the core completely covers this 
smaller conical body, leaving only the flat surface of the latter, corresponding 
to the basal plane of the cone, uncovered. The front end, or base, of the 
smaller conical body, and the tubular rind together form a smooth anterior 
Text-fig. A. Diagrammatic representation of the axial core at the anterior end of the body of 
Teratonympha. 1, tubular rind; 2, outer cone; 3, inner cone; 4, vertical partition. 
surface for the whole structure; but the central cone is a little more advanced 
in position than its surrounding tube, so that the frontal surface of the main 
part of the axis slopes gradually from the junction of the two cones towards 
the boundary between the external cone and the tubular rind. The interval 
between the core and the rind is more or less spacious, and is filled by a 
structureless protoplasmic substance of dense consistency. Though the rind 
and the greater portion of the conical core seem completely separated from 
each other, careful observations show that there is a distinct vertical partition 
on both sides, stretching from the posterior end of the whole axis to the point 
where the tubular rind and the conical core are in contact anteriorly. The 
two partitions are so situated as to lie in one plane, or nearly so, and divide 
the space between the apex of the cone and the tube into two nearly equal 
halves. 
The tubular rind takes iron-haematoxylin very feebly or not at all, ex¬ 
cepting a zone of limited breadth at the inner surface, which is stained rather 
