178 TRANSACTIONS OF THE [may 11, 
plane, and upon reaching the top of the ear bends suddenly 
toward the median plane, passes through the wall of the cap- 
sule and enters an oblong depression in the top of the skull. 
The duct now expands into a flattened sack which makes four 
bends and opens externally close to the occipital portion of the 
lateral line. Whether the ductus endolymphaticus connects or 
communicates with the lateral line system, I cannot say. One 
dissection gave evidence that such was the case and also that a 
nerve communicated with the terminal pore, but as yet I have 
not been able to make control dissections. 
From the dorsal wall of the main body chambers of the cap- 
sular cavity there projects downward a piece of cartilage which is 
firmly attached to the dorsal wall of the sacculus (s.) near the 
center. In the vicinity of the lagena (1.) there is also a point 
where the wall of the sacculus is closely attached to the wall of 
the capsule. 
LAGENA. 
The lagena is an outgrowth from the posterior part of the sac- 
culus (s.). It is a small rounded sack projecting downward 
paralell to the median plane. It extends about 1 mm. below the 
lower surface of the sacculus. It seems to be formed by a con- 
striction in the sacculus as well as by an outgrowth of its pos- 
terior wall. The lagena presents more and greater variation 
than any other part of the ear. 
UTRICULUS. 
The utriculus (u.) is an elongated flattened tube extending 
from the anterior ampulla (a. a. Figs. 1 and 5) across the upper 
part of the sacculus. Then curving upward it becomes thicker 
and broader and continues upward until it connects with the 
horizontal and anterior canals. As before noticed, the utriculus 
(u.) is on the dorsal wall of the sacculus above the diagonal line 
of depression (** Fig. 5), and rests on the dorsal or outer wall 
of the ductus endolymphaticus. The utriculus communicates 
with the sacculus by means of the canalis utriculo-saccularis, 
which is a long slit-like opening. There is no communication 
between the utriculus and the ductus endolymphaticus except 
through the sacculus or recessus utriculus (7. u.), because the 
partition which forms the base of the utriculus, and also the 
lower lip of the opening between the utriculus and sacculus, lies 
upon and adheres closely to the dorsal wall of the ductus en- 
dolymphaticus. 
Sinus UTRicuLus. 
The upper part of the utriculus (u.) is somewhat thicker and 
