THE ORGAN OF JACOBSON IN THE RABBIT. 568 
taere are never any cilia to be met with onthe surface of the 
epithelium, and in this respect there does really exist a remark- 
able difference between the rabbit’s and guinea-pig’s Jacobson’s 
organ. 
The epithelium of the lateral wall now under consideration is 
always infiltrated with lymph-corpuscles, each with two or three 
small nuclei ; these cells evidently migrate from the subepithelial 
layer into the epithelium; they are found in all parts of the 
epithelium. 
(4) The subepithelial layer contains always a great number 
of lymph-corpuscles, both in the glandfold and beyond it ; the 
lymph-corpuseles are relatively large cells, each of them possessed 
of a well-formed cell body. Where they are crowded together 
they appear pressed against one other, and therefore more or less 
polyhedral in outline. 
(c) The elastic layer is composed chiefly of networks of fine 
elastic fibrils extending in a direction parallel to the long axis of 
the organ. ‘This layer, increases in thickness (to almost double) 
as we pass backwards ; it is always very conspicuous in transverse 
sections stained with dyes, since its bright fibres do not stain, 
and therefore contrast well both with the subepithelial layer and 
with the cavernous layer outside. ‘The elastic layer is evidently 
the layer in which the muscular fibres of the cavernous layer 
insert themselves. b 
(2) The cavernous layer. This is the most conspicuous part of 
the lateral wall. As mentioned above, it increases both in thick- 
ness and breadth as we pass backwards (compare figs. 4 to 9). 
Tts venous sinuses take up a plexus of small vessels, chiefly veins, 
situated close to the elastic layer. The sinuses extend in a longi- 
tudinal direction and are separated from one another by, or rather 
are embedded in a tissue, which consists pre-eminently of mus- 
cular substance. ‘This is arranged in bundles of various sizes, 
directed chiefly ina radiating manner from the periphery of the 
organ, 7.¢, from the outer wall of Jacobson’s cartilage towards 
the lumen of the organ, and connected into plexuses. Between 
these bundles we meet always a few bundles running in an oblique 
or even longitudinal direction. In preparations prepared with 
spirit the muscular tissue does not differ from non-striped mus- 
cular tissue, but in osmic acid specimens, hardened afterwards in 
chromic acid, the elements of this muscular tissue appear ma- 
terially to differ from ordinary non-striped muscular tissue. We 
find, namely, that the individual elements are twice and three 
times as thick as ordinary non-striped muscle ceils ; that they are 
composed of coarse fibrille, and that they appear much longer 
and each to possess a number of nuclei ; further, that they appear 
as if branched and connected into a network, so that they resemble 
