496 
PAUL PELSENEER. 
I shall examine these different parts successively. 
1. Muscles of the Buccal Cones. — The muscular cells 
are unstriped, elongated, and contain a nucleus of a prismatic 
form (fig. 13, b'). The muscular external layer of annular fibres 
is much less developed than the internal layer. This latter is 
very powerful, which explains the great extensibility of the 
cones. The longitudinal fibres are united in distinct groups 
(fig. 13, b). 
2. Glandular Internal Cells. — A transversal section of 
one of the cones shows that their interior is filled with cells 
united in groups (fig. 11, b). In the lower half of the cone 
the centre of the sections is empty, and the cells are only 
found against the longitudinal muscular layer. 
A longitudinal section will make this disposition better 
understood (fig. 12). The cells in question are united in 
elongated groups, having the form of follicles. Each cell 
possesses a proper prolongation, which is continued to the 
epithelial covering of the cone. Each of these groups possesses 
a basement membrane of connective nature, but the different 
groups are pressed one against the other without one being 
able to see between them any free connective tissue, under 
the form of cells or fibres. The spaces which are seen in 
several places, on the figure 10 of the plate, proceed from dis- 
placements which occur during the preparation of the sections. 
Among the groups which have been displaced I have not seen 
any traces of connective tissue. 
These groups of secreting cells do not constitute a gland, 
for nowhere on any section, longitudinal (fig. 16) or transversal 
(fig. 17), can a lumen be seen, nor efferent duct. Each cell 
is an independent unicellular gland. The contents of these 
cells is a slightly granular substance. The nucleus is large 
and spherical ; it gives indications of its reticulated structure, 
but not clearly enough to make drawings of them showing this 
structure. 
The cells situated at the interior extremity of the groups 
have excessively long prolongations (fig. 16, d) ; the cells 
situated near the muscular layer have, on the contrary, much 
