224 DR. E. KLEIN. 
In my first paper I have shown that the layer of (serous) 
glands is situated outside the cavernous layer, and extends 
in the lateral wall from the lower sulcus to the upper sulcus, 
but its bulk lies about the lower sulcus, into which the ducts 
chiefly open (see figs. 1 and 2 of my former paper). As we 
pass backwards, but long before the extremity of the organ 
is reached, we find the area in which the glands extend 
considerably increased, for many glands are now found also 
about the upper sulcus, and their ducts open into this latter. 
In the part which we just before described as the poste- 
rior extremity, viz. the narrow hind part with the cylindrical 
lumen, and without any sensory epithelium on the median 
wall, we find the layer of glands forming a complete invest- 
ment and occupying almost the whole periphery of the organ 
(see fig. 7). 
Another difference between the posterior section of the 
organ and the rest lies in the change the cavernous tissue 
undergoes in that extremity. As is shown in fig. 7, its 
position is not the same that it was before (compare figs. | 
and 2 of my first memoir), viz. occupying the lateral wall 
only, for, owing to the altered position of the luamen—this 
latter being not vertically but obliquely placed—the ca- 
vernous tissue now occupies the lower wall. At the same 
time the number of vessels and the amount of non-striped 
muscle tissue are greatly increased, although the individual 
vessels are not of so large a size as in preceding portions of 
the organ. 
The plexus of non-striped muscular tissue forming the 
matrix of the cavernous layer is best developed in the extre- 
mity itself, and, together with the plexus of veins of the 
cavernous layer and the gland layer outside, extends for 
some little distance behind the cecal end. In lorgitudinal 
sections comprising the posterior portion of the organ of 
Jacobson, these plexuses of bundles of non-striped muscular 
cells, and of veins between them, is very finely seen. 
The tube which I described and figured in fig. 1! in my 
first memoir was there named the “ accessory organ of 
Jacobson.” But this is the naso-lachrymal duct; this was 
suggested to me through the kindness of Dr. Allen Thom- 
son, by Prof. Kolliker, of Wiirzburg, and on careful dissec- 
tion I have convinced myself that this is really the case. 
It extends anteriorly and posteriorly considerably beyond 
the region of the organ of Jacobson. Anteriorly the naso- 
1 In the text, p. 106, it is erroneously referred to as “at § in fig. 1,” 
it should read ‘at 9 in fig. Ry 
