Fig. 8.
IS the Basis of the Skull with the First Vertebra of the Neck remain∣ing on it, together with divers Muscles and other Parts.
A, B, C C, D D, The First Vertebra of the Neck: A, its Fore-part, behind which, the Tooth-like Process of the Second Vertebra is plac'd; B, its Back part wanting a Spinal Process where the Musculi Recti Minores Postici Arise; C C, The Transverse Process's: D D, Two somewhat Oval Process's of the First Vertebra, which Move Side∣ways on the like Process's on the Upper Part of the Second Verte∣bra of the Neck.
E, A Cavity immediatly behind the Fore-part of the First Vertebra, Fenc'd with a strong Ligament Backwards next the Medulla Spinalis, in which the Tooth-like Process of the Second Vertebra Tab. 93. Fig. 3, 4. A A, is receiv'd.
F, The Great Foramen, through which the Medulla Spinalis Descends from the Head.
G, A Small Muscle, which from its Position I call Rectus Lateralis: I first met with it in Dissection, some time since, and afterwards found it was partly Mention'd by Galen, and De∣scrib'd by Fallōppius: It Arises from the Superior Part of the Extremity of the Transverse Pro∣cess of the First Vertebra of the Neck, and Ascends directly to its Implantation in the Os Occipitis; when it Acts, it Nods the Head Laterally.
H, The Musculus Rectus Anterior Minor, so call'd from its Progress, Situation and Size, it being much less than the Rectus Major, Tab. 18. L L. It Arises from the Fore-part of the First Vertebra, and is Inserted to the Appendix of the Os Occipisis: This with its Partner Nod the Head Forewards, and may be term'd Annuentes.
I I, The Perforations in the Transverie Process's of the First Vertebra, in which the Trunks of the Vertebral Arteries and Veins Pass.
K K, The Trunks of the Vertebral Arteries in their Contorted Passage between the Trans∣verse Process of the First Vertebra and Great Foramen (F) of the Os Occipitis.
L L, The Mamiform Process's.
M M, The Cartilages of the Meatus Auditorius.
N N, A Probe Inserted into the Meatus à Palato ad Aurem. This Passage from the Fauces ad∣mits the Air to Pass from thence into the Cavity of the Tympanum, whereby the Membra••ea Tympani becomes more Distended, and the least Impetus of the outward Air Shakes it, toge∣ther with its little Bones that are Contiguous to it. Besides this Passage into the Tympanum, there is another Passage out of it, by the Upper Part of the Membrana Tympani into the Meatus Auditorius, by which some in holding their Nostrils and Mouths, and forcing up their Breath, can move a small Feather or the Flame of a Candle, when held near the Outward Ear; in others it's still Opener, and they can Blow Smoke out at their Ears. Tho' this Passage thro' the Tympanum is not commonly so Open as in the First Case, yet naturally there is a Small Passage by the Upper Part of the Membrana Tympani into the Measus Auditorius, which seems necessary, to the End when the Tympamon is Fill'd with Air, any Sudden Impetus of the Ex∣ternal Air should not Violate the Membrana Tympani. The Meatus à Palato ad Aurem do's not only Convey Air into the Tympamon, but (constantly remaining Open) it Admits of a Flu∣ctuation of the Contain'd Air of the Tympamon, as well as a Fresh Supply: If this Passage is Straiten'd, a Difficulty of Hearing necessarily Follows; if it is totally Obstructed, a Deafness; in which Case, the Taking of Sneezing Powders gives Relief.
O, The Glandulous Membrane Continu'd from the Foramina Narium to the Inside of the Fauces.
P P, The Processus Scyloides.
Q, The Carotid Artery Cut off near its Entrance into the Os Petrosum.
R R, The Lower Parts of the Ossa Iugalia.
S, A Cartilaginous Body lying in the Depressure of the Os Temporum, where the Processus Condyliformis of the Lower Jaw is Articulated.
T, The same Intermediate Cartilage of the Articulation Rais'd.
V, The Smooth Sinus in the Os Temporale, which Receiv'd the last mention'd Cartilage.
t, Part of the Mucelaginous Gland of this Articulation, Clearing to the above-mention'd Cartilage.
W, The Upper Part of the Os Temporale Cut off.
X, The Os Occipitis, in like Manner Saw'd off.
Y, The Musculus Occipitalis, as it Arises from that Part of the Os Occipitis, where the Muscles of the Head are Inserted, whence Mounting it, soon becomes Tendinous, and Marches on the Sincipus, where it's Join'd with the Tendon of the Fromalis: Unless it may be Suppos'd, that the Occipital and Frontal Muscles are One Biventral Muscle, Arising from the Occiput and Inserted to the Lower Part of the Skin of the Fore-head, and being Fasten'd to the Hairy-scalp, Moves it Forewards and Backwards, as well as Lifts up the Lower Part of the Forehead with the Eyebrows.
Z Z, The Thinner Part of the Os Occipitis, where the Muscles of the Head are Inserted.
a, The Gargareon Supported by the Probe, N N, Inserted into the Meatus à Palato ad Aurem.
b b, The little Glandules, which Appear in Cutting the Fauces from hence.
c c, The Extremity of the Processus Pterygoides, or more properly the Extremity of a Small Slender Process above the Processus Pterygoides in this Position of the Skull; since Anatomists in Describing the Muscles of the Uvrela have call'd this Process Pterigoides or Aliformis, we shall still Retain the same Name, tho' the Aliform Process's Exprest, Tab. 92. Fig. 2. K, are Distinct Pro∣cess's, and no ways like these.
dd, The Musculi Sphenopirrigostaphilini, so call'd from their Origin, Progress, and Insertion: they are also call'd Pterigopalatini and Sphenoterigopalatini; they Arise Fleshy from an Acute Process of the Os Sphenoides Exprest Appen. Fig. 15. H. whence they Pass to the Processus Ptery∣goides, c c, where they become Tendinous, and are Reflected over those Process's to their Inser∣tions on the Fore-part of the Gargareon: When these Act, they Draw the Fore-part of the Garga∣reus towards the Pterigoid Process's, whereby it's pull'd somewhat Upwards, as well as Forewards.
e e, The Sphenostaphilini: These Arise from the same Process's of the Os Sphenoides with the for∣mer, and are Inserted on the Back-part of the Gargareon Opposite to the Former. These Draw the Uvula Upwards and Backwards, whereby it Prevents the Ascent of the Aliment into the Fora∣mina Nariton in Deglutition, as it Happens in those in whom the Uvula is wanting.
f, The Musculus Pterygoideus Externus Left at its Origin, at the External Part of the Processus Pterygoides, as well as the Upper Part of the Os Sphenoides it self; whence it Passes Backwards to its Insertion at the Neck of the Processus Condyloides of the Lower-Jaw. When this and its Partner Act they Draw the Lower-Jaw Forewards, whereby the Fore-teeth of the Lower-Jaw are Driven beyond those of the Superior, as Falloppius Observes.
g, The Musculus Pterygoideus Internus also Free'd from the Lower-Jaw, and Left at its Origin: Tab. 15. Fig. 2. N. It's Represented at its Insertion.
h, Some Appearance of the Septum Narium Backwards.
i i, The Denies Molares.
k k, The Canini.
l, The In••isores.
m, The Glandulae Labiorum, as they Appear in the Inside of the Upper Lip. Under the In∣Internal Membrane of the Mouth; each of these Glands has an Excretory Duct, which Perfo∣rates the Membrane of the Mouth at a small Papilla, by which a Salival Humor is Emitted in∣to the Mouth: The like Glands may be seen on the Inside of the Cheeks.
n, The Tip of the Nose.
o, The Hairs of the Palpabrae.