314 JOURNAL OF COMPARATIVE NEUROLOGY. 
that there were apparently two methods of connection of the 
operculum with the suspensorium (quadratum). Thus, WIEpD- 
ERSHEIM gives as the universal condition, that the nervus facialis 
passes above the suspensorio-opercular connection ; Hux try de- 
scribed a suspensorio-stapedial (opercular) ligament wxder the 
facial nerve; Hassr, in Siredon (Amblystoma) described the 
nerve as under the columella; while the statements of PARKER 
are not always clear, though it is evident that in the different 
Urodela both relations of columella or suspensorio-opercular 
ligament and nerve were described. 
The study of the relations in the three forms above men- 
tioned, to which Proteus anguineus, Amphiuma means, and 
Amblystoma tigrinum (larva) may. be added, has shown that in 
all except Necturus, the nervus facialis passes below (ventrad 
to or cephalad of ) the suspensorio-opercular connection. In 
Necturus, the ramus jugularis facialis passes above (dorsad to) 
the ligament, the remainder of the nerve, i. e. ramus mandibu- 
laris externus and internus, and ramus palatinus being below 
(ventrad or cephalad to) this structure. Furthermore, in these 
three forms, the columella or ligament passes from the opercu- 
lum to the bone which lies partly upon the ear capsule and 
partly upon the external surface of the quadratum—and which, 
as far as I can judge from the evidence at hand, I regard asa 
squamosum ;—and not (primarily) to the cartilage of the quad- 
ratum as heretofore stated. This isa fact of considerable mor- 
phological importance. A more detailed description of the 
relations in the forms follows : 
Necturus Maculatus.. In this form Hux.ey' described the 
‘‘suspensorio-stapedial ligament’ as arising from the ‘‘middle 
of the posterior edge of the quadratum—and passing upwards 
and backwards to the stapes. The Hyomandibular branch of 
the seventh nerve passes passes above this ligament to its dis- 
tribution just as it passes above the columella auris in the Frog.”’ 
WIEDERSHEIM made no different statement of relations. This 
structure described by Hux.ey, which was presumably a sheet of 
VOps ctit-p. 192. 
