The roof of the braincase in our specimen seems to have been detached from the underlying otic capsules and the occipital wall.
Internally, it must lie against the oticcapsule below the tabular, partially concealing the stapes.
The single otic capsule that can be seen (the right) is massively built, apparently ossified in one piece, with a shallow dorsomedial excavation, probably the vestige of a supratemporal fossa.
On the other hand, an adult animal of pigmy size might be expected to have large orbits, large otic capsules and a large foramen magnum.
The length is appropriate to fit between the lateral face of the otic capsule and the dorsal edge of the quadrate; the wider head rests on a posterodorsal concavity on the otic capsule, and the smaller fits a lower, more anterior pit.
The form of the stapes, tabular and otic notch suggest a functional tympanic membrane, which could not have occurred in a gill-breathing larva.
The dorsal part of the bone flares out and down, forming a small otic notch at a point halfway back.
The otic capsules appear to have rested against lateral projections of the basioccipital.
Anterior to the otic capsule the lateral wall of the braincase cannot be seen, and may not have been ossified.
The posterior wall of the otic capsule we have designated opisthotic in the figure.
This articular surface probably fitted on a lateral process extending from the roof of the neurocranium, over the front of the otic capsule.
The otic ganglion is placed below the base of the skull, and also connects with the carotid plexus.
The medial part forms the ventrolateral ledge of the otic capsule (vl.
The otic process extends along the medial surface of the squamosal from the dorsolateral edge of the pseudobasal process, and then expands medially to meet the bony edge of the otic capsule and form the crista parotica.
The operculum expands medially to merge with the main part of the otic capsule (Fig.
Posteriorly, endochondral ossification is restricted in the dorsal part of the otic capsule but somewhat increased in the floor of the capsule.
The posterior terminus of the medial branch of the pterygoid lies ventral to the lateral part of the otic capsule.
Transverse sections through otic capsule: 18) at level of posterior acoustic foramen; 19) at level of jugular foramen.
Transverse sections throughotic region: 16) at level of prootic foramen; 17) at level of anterior acoustic foramen.
The anteroventral edge of theotic capsule remains cartilaginous.
Examine the otic capsule by taking successive slices through it to show the labyrinth of the ear.
Mark on the skull with long needles and flag-labels the sphenethmoid and the pro-otic bones.
The shaded part in 4 is the -otic capsule- [tympanum].
In front of the oticcapsule is the paired pro-otic bone (p.
It will be learnt from these latter that this bar is joined in front to the cranium behind the nasal organ, and behind to the otic capsule.
Its position is, of course, beneath the squamosal, and just outside the otic capsule.
It is situated internal to the right-angle between the two vertical canals, and reaches to the surface of the otic capsule.
The Brain Case-- Of the frog is a cylindrical box, from which the otic capsules project conspicuously on either side.
Further, the otic capsules are fusing with the brain-case.
The deep groove figured lateral to the otic capsule is the connecting line of the orbital and anterior cardinal sinuses; the outline of the anterior cardinal sinus in this figure and in Figure 1 is roughly indicated by a dotted line.
In the lower forms it is a hollow membranous structure, embedded in a mass of cartilage, the otic capsule; in the mammal the latter is entirely ossified, to form the periotic bone.
The structure of this is easily made out by clearingotic capsule and cutting slices of the cartilage in the Dog-Fish (e.
The Origin of the Pro-otic Segmentation: the Meaning of the Trigeminal and Eye-muscle Nerves," vol.
The comparison of the eye-muscles of the vertebrate with the dorso-ventral segmented muscles of the invertebrate makes the number and nature of the pro-otic segments much clearer.
In this chapter the consideration of the pro-otic segments is commenced, that is, the segments supplied by the trigeminal (V.
This inclusion of the facial nerve into the pro-otic group of nerves forms one of the main reasons why this group has been supposed to have originally supplied gill-pouch segments, for the hyoid segment is clearly associated with branchiae.
As already mentioned, the facial nerve is usually included in the trigeminal or pro-otic group of nerves, the opisthotic group being confined to the glossopharyngeal and vagus.
On the anterolateral surface of the prootic, branches of the trigeminal nerve pass through three foramina whereas the facial nerve passes through the single posterior foramen near the otic notch.
Each exoccipital also forms the posterior part of the otic notch, which traverses the exoccipital.
Laterally this bone is deeply emarginate; posteriorly it forms a large part of the otic notch, through which the columella passes.
But at one stage in the general reduction of the skull in the ancestry of both groups, a condition similar to that in Protobatrachus may have characterized the otic region, long before the Triassic.
On the other hand, Necturus and Proteus alone among living salamanders have a distinct opisthotic on the posterior wall of the otic capsule (Fig.
Since the remainder of the posterior wall of the otic capsule consists of cartilage, meeting the exoccipital, it may be that the opisthotic becomes the operculum in frogs.
Although the stapes and otic region are readily visible in a number of labyrinthodonts and lepospondyls, no indication of an operculum seems to be reported among them.
The exoccipital extends laterally, occupying the posterior face of the otic capsule.
Between it and the otostapes is a small disc, usually ossified, the operculum, which normally fits loosely in a portion of the fenestral membrane, and is developed from the otic capsule.
VII is the facial nerve) ] In temnospondylous Amphibia the tympanum generally occupied an otic notch, at a high level on the skull, bordered dorsomedially by the tabular and ventrolaterally by the squamosal.
Therefore the Proteidae probably are not derived from the general stem of other salamanders, but diverged sufficiently long ago that the bones of the otic region were reduced on a different pattern.
The medial ramus of the pterygoid does not articulate with the otic capsule, and the parasphenoid alae are laterally, rather than posterolaterally, oriented.
The anterior rami terminate at about the mid-level of the orbit, and the medial rami articulate firmly with the anterolateral corner of the otic capsule.
The squamosals of all species are moderately large structures having otic plates that overlie the lateral portion of the cristae paroticae.
At this stage we may call the remaining cavity of the original otic vesicle, into which all the above parts open, the utriculus.
Its upper end exhibits a tendency to divide into two processes, corresponding with the pedicle and otic processes of the Amphibia.
Lying close to the inner side of the otic vesicle is seen the cochlear ganglion GC; on the left side the auditory nerve G and its connection N with the hind-brain are also shewn.
Thus the epi-otic often unites with the supra-occipital, and the opisthotic with the exoccipital.
It commences to ossify from three centres corresponding to the pro-otic, epi-otic and opisthotic of lower skulls, such as those of the Turtle and Crocodile.
Piercing the posterior end of the pterygoid is the prominent opening of the carotid canal; a bristle passed into this hole emerges through a foramen lying between the pro-otic and the alisphenoid process of the pterygoid.
They are connected by the supratemporal with the epi-otic and opisthotic regions of the cranium.
Between the pro-otic and opisthotic as seen in a longitudinal section of the skull is a large opening constricted in the middle.
The pro-otic lies in front of the exoccipital and together with the opisthotic forms the hind border of the fenestra ovalis.
Both epi-otic and pterotic are drawn out into rather prominent backwardly-projecting processes.
The epi-otic regions of the skull are ossified, forming a pair of large bones which lie external to, and distinct from, the exoccipitals.
The auditory or periotic capsule of the turtle is rather large and its walls are well ossified, epi-otic, pro-otic and opisthotic bones being present.
The insertion is fleshy on the posteromedial edge of the body of the quadrate and the orbital process of the quadrate and on the otic process of the quadrate.
The muscle also has an origin from the otic process of the quadrate, partly fleshy and partly by a slight aponeurosis.
In some non-passerine species as well as in certain passerines the muscle also serves to raise the upper jaw by acting on the quadrate, which is capable of rotating vertically on its otic process.
It receives fibers on its ventral surface from the otic process of the quadrate, and on its dorsal surface gives rise to fibers that insert on the dorsal aponeurosis (figs.
The origin is fleshy from the medial surface of the temporal fossa, the posterior wall of the orbit and the otic process of the quadrate.
The bone initiating the movement is the quadrate, which is hinged posteriorly by its otic process and which ordinarily swings up or down depending on the muscle or muscles being contracted at any given moment.
In the columbids the quadrate has a bifurcated otic process that functions as the hinge.
The others are dying," said Mjly, blinking her otic nerves eerily.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "otic" in a variety of sentences. We hope that you will now be able to make sentences using this word.
