398 THE NASAL REGION IN EUTAENIA. 
(2) The capillary plexus, which is directly continuous with that 
mentioned above ; the rest of the mucosa is occupied by 
(3) The abundant pigment cells which spread out at the junction 
of floor and roof to surround the cellular columns in the mode de- 
scribed above.” 
Prof. Wright’s and my own studies further on the same subject 
have'given the following : 
The sensory stratum is divided into (1) the cellular columns 
already mentioned, oblong in section in the body of the organ, but at 
its posterior termination, polygonal, completely surrounded by the 
constricting plexus at all but one point, where their cells pass 
gradually over into those of (2) the sensory portion adjacent to the 
superticial stratum, and consisting of two or three layers, The 
cells of the second portion of this stratum do not exhibit any differ- 
ence from the sensory cells of the nasal passage, except that the 
nucleus in each and the portion of the cell containing it are more or 
less fusiform. In those of the columns, however, the central and 
peripheral processes are undistinguishable, so far as shape is con- 
cerned, both exceedingly delicate and wavy in their course. When 
the columns, macerated in Miiller’s Fluid, are teased out, minute 
portions will be frequently seen through which the delicate processes 
pass in every direction. The nucleus in each is large, distinct and 
quite spherical, with little protoplasm surrounding it. Through the 
point of the connection of the columns with the rest of the sensory 
cells, their peripheral processes reach down between the latter to 
the lumen of the organ and terminate like them. 
The terminations of the sensory cells in the lumen are knob-like 
and about one-fourth the length of the sense-hairs in the nasal pas- 
sage. With such a length all capability of movement is absent- 
There is no swelling to be observed at the base of each. 
In the superficial stratum the cells have the same shape as in the 
nasal cavity. They are provided with the same distinct border 
structure, through which the sensory terminations push. Of any 
prolongation of the protoplasm of the superticial cells beyond this 
border structure no convincing proof has been met with as yet. In 
several cases a faint striation parallel with the cylindrical cell was 
observed at its border. This was replaced by a delicate granular 
precipitate in macerated specimens. The number of cases in which 
such a striation was observed, were few in comparison to the amount 
of material examined. It is, however, quite probable that the cylin- 
drical cells are provided with cilia as excessively fine as these of the 
nasal cavity. 
The border structure must be regarded as the homologue of the 
membrana limitans olfactoria of the nasal cavity. 
