498 
PAUL PELSENEER. 
thickness, longitudinal striae which are strongly coloured by the 
haematoxylin. 
Between the cellular substance and the membrane we find 
the fibroid secretion ( d ) of the glandular cells which occupy 
the interior of the cone. 
Each of the epithelial cells so constituted has been taken by 
Eschricht for a sucker. 
Under each epithelial group, at the surface of the annular 
muscular layer, or even between the fibres of the latter, is 
found a large sensorial cell (i), which sends a prolongation (&) 
across the subepithelial connective tissue. This prolongation 
continues between the epithelial cells and terminates freely at 
the surface of the cone. 
These sensorial cells possess a large refracting nucleus (j), 
with a strongly colourable nucleolus. 
The prolongation, rather narrow in the connective tissue, 
enlarges a little between the epithelial cells and constitutes a 
rod in the form of an elongated cone (/), with the base turned 
towards the surface. The part of the prolongation, contained 
in the connective tissue, presents in some series of sections 
strongly coloured, a very special aspect; it appears to be reti- 
culated (fig. 14, a). The conical part, situated between the 
epithelial cells, presents numerous longitudinal striae. The 
rod is terminated by a kind of small horizontal rather thin disc 
(fig. 13, m), which is more strongly coloured than the sub- 
jacent part. This disc does not bear cilia such as we see upon 
the extremity of some sensorial cells. I do not think that in 
the specimens I have studied, the sensorial cells have lost their 
ciliary covering, for the other parts of the body which bear 
cilise have their ciliary investment intact. 
At the prolongation of the sensorial cell, towards the base of 
the epithelial cells, we find a spherical or ovoid refracting body 
(: n ) joined to it, whose membrane seems rather thick, and in 
the interior of which we find a corpuscle deeply coloured by 
the hsematoxylin. 
The complicated structure of these epithelial groups is very 
clearly shown by a series of transversal sections of these groups, 
