Book One -- The things that sustain and support the entire body, and what braces and attaches them all. [the bones and the ligaments that interconnect them] | Chapter 12 On The Foramina of the Head and the Upper Maxilla

[Figure Legend]

A 1 12 Foramen [f. supraorbitale] carved at the middle of the brow, through which a branch [n. supraorbitalis] (N in fig. 2 preceding Ch. 2, Bk. 4, and H in the 4th table of muscles) of the lesser root [n. ophthalmicus] of the third pair [n. trigeminus] of cerebral nerves [nn. craniales] is dispersed from the eye socket [orbita] to the muscular skin of the forehead. 13 This foramen exists on either side, not always completely round, but often just a depression appears, carved out like a semicircle. Sometimes a foramen is seen on one side but only a semicircular depression on the other, as here in the first figure. 14 This foramen belongs to the frontal bone, which is marked with a number of I’s in the first figure of this chapter. It is not necessary for me also to mark a bone here in the text or in the margin when the character marking the foramen readily shows also the bone into which it is carved.
B 1 Foramen [f. infraorbitale] through which a branch [n. infraorbitalis] (O in fig. 2, Ch. 2, Bk. 4 and I in the 4th table of muscles) from the aforementioned lesser root [n. maxillaris] of the third pair of cerebral nerves drops from the eye socket into the cheeks toward the muscles of the upper lip and the alae of the nose. This foramen is carved like an elongated passage in the fourth bone [maxilla] of the upper maxilla, and its path is hollowed deep in the bone in the anterior portion of the maxilla where B is placed in the first figure. 15 Indeed, through the socket of the eye it is covered only by a thin and very scaly bone; we have marked this region L, 16 visible in the eye socket.
C 1 A foramen [fossa sacci lacrimalis] larger than the one just mentioned, which extends straight down from the large or inner angle of the orbit into the cavity of the nostrils, equally shared by the the second [os lacrimale] and fourth bones [maxilla] of the maxilla [upper jaw]. This foramen provides a path to a small portion (P in figure 2, Chapter 2, Book 4) [n. nasociliaris] of the lesser root [n. ophthalmicus] of the third pair of cerebral nerves, and is believed to transmit 17 to the nostrils some of the phlegm 18 that flows from the brain to the eye socket. Besides this foramen, another larger one [fossa pterygopalatina] is provided for the flow of phlegm from the eye socket into the nasal cavity, 19 and from here more to the the throat than the nose. Since this lies more deeply hidden and can in no way be displayed in the preceding illustrations, see the fourth figure at the front of Chapter Six, from which we have cut out the jugal bone (to place the hollow of the temple more exactly next to the eyes) and added a F to that illustration so that at least the location of this foramen incised in the cuneiform bone could be shown. The more this is out of sight in skulls, the less surprising that noteworthy as it is, it has escaped the notice of leading anatomists.

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D 1 , 2 This foramen [fissura orbitalis inferior] 20 is easily the largest of all that are seen in the eye socket, and gives passage to a small branch (Q in fig. 2, Ch. 2, Bk. 4 21 ) of the already oft-mentioned lesser root [n. maxillaris] of the third pair of cerebral nerves cerebral nerve [n. trigeminus], extending from the eye socket into the temporal and masseter muscles. 22 This long, open foramen is not carved only for a small nerve: it also provides strength to the beginning of the temporal muscle. In addition, it furnishes a path for phlegm flowing down to the larger foramen 23 (which we have marked F) extending into the nasal cavity. Indeed, it seems prepared for a certain small nerve (d in fig. 2, Ch. 2, Bk. 4) which we were the first to note runs next to the root of the fifth pair of cerebral nerves [n. facialis and n. vestibulocochlearis]. That little nerve extends through its own foramen a little farther back — to be labeled H [f. zygomatico-orbitale] — into the temporal muscle, the masseter, and the muscle [m. pterygoideus medialis] concealed in the mouth that assists in raising the jaw. This fissure or elongated foramen, labeled D, extends to the cuneiform bone and the fourth bone of the upper maxilla.
E 1 , 3 The E placed in the third figure and in both eye sockets of the first figure marks the foramen [canalis opticus] that is highest in the root or vertex of the eye socket and is incised in the cuneiform bone; outside the point where it faces the eye socket it appears quite round, corresponding in size to the optic nerve (N, O in fig. 13, Bk. 7)(for which it is carved out). But inside the skull, where it nears the brain, it has on the outside a slight but sharp angle which is made for a small vein [arteria ophthalmica] that exits here with the optic nerve. The letter g marks this angle [processus clinoideus anterior]. It lies between E and g in the third figure of this chapter.
F 3 The junction [chiasma opticum] of the optic nerves (M in fig. 13, Bk. 7) rests in this pocket [sulcus prechiamaticus] carved in the cuneiform bone.
G 1 , 3 G is in the left eye socket of figure one, and in the third figure it occupies the right side of the illustration because in the left side the foramen [fissura orbitalis superior] so identified is not visible since we have tilted the skull to the side in order somehow to see this very foramen.

Because this foramen [fissura orbitalis superior] is hard to see in the figures of this chapter, I have drawn a picture here of the foramen of the right side, marking its lower portion d, and its upper part, the angle of the foramen, e. The foramen of either side is clearly visible in the eighth figure of Chapter 6.

It is carved into the cuneiform bone, and in its lower part it is a little less than completely round, while in its upper part it ends in a sharp, long, and narrow angle. This foramen, though it seemed otherwise to Galen, is larger than the the foramen [canalis opticus] of the optic nerve. 24 If it were perfectly round like the optic foramen, it would easily be three or four times larger. Nevertheless, its lower part, which we have said is a little less than completely round, still far surpasses the size of the foramen of the optic nerve. It is hollowed for the sake of the second pair of cerebral nerves [n. oculomotorius] (G in figure 14, Book 7) as they proceed into the eye socket to move the muscles of the eye, 25 and secondly for the lesser root [n. ophthalmicus] of the third pair [n. trigeminus] of cerebral nerves (H [n. trochlearis] in the same figure), which is distributed to the skin of the forehead, to the muscles on the face of the upper maxilla, the nostrils, and the muscles [mm. temporalis, masseter, pterygoideus medialis] that raise the lower maxilla. 26 These roots drop through the lower part of the foramen together with the major branch [arteria carotis interna] (x in the figure for Chapter 14, Book 3 27 ) of the sleep artery, which some allege forms the reticular plexus in man. 28 But in fact a vein [vena ophthalmica superior] (G in the same figure and H in fig. 13, Bk. 7 29 ) is at this point distributed from the eye socket, away from the veins that go to the temporal muscle 30 and through the upper part of the foramen where the foramen [fissura orbitalis superior] is compressed into a long, narrow angle, 31 to the hard membrane [dura mater]; and for its distribution in the base of the skull, it has pockets carved out there corresponding to the swellings of the small veins; these are visible in that part of the skull where z is written in figure 3. This large foramen is by no means carved out only for these nerves, 32 the vein [v. ophthalmica superior], and the large artery [a. ophthalmica] just mentioned: it is also for phlegm that flows into the eye socket from the brain and from hence into the cavity of the nostrils, as dissection brilliantly and delightfully shows, 33 since by no account does this foramen’s great size appear so small as those nerves, the vein, and the artery.
H 1 , 3 The round foramen [f. rotundum], going farther inside the bone than the two just mentioned, and narrower. 34 This, with others, is carved in the cuneiform bone [os sphenoidale] for the small nerve [n. abducens] (L in fig. 14, Bk. 7) that you will hear originates not far from the principal root of the fifth pair. 35 The one placed beneath G on the right side of the third figure appears a little larger than the one on the left side, because sometimes, besides that nerve, it also transmits the small nerve that is the lesser root of the third pair [n. trochlearis] (H in fig. 14, Bk. 7) which we mentioned a little earlier is brought down through the foramen [fissura orbitalis superior] marked G.
I 3 At this location in the eighth bone [lamina cribrosa ossis ethmoidalis] of the head many small foramina [foramina cribrosa] (E in figure 12, Book 7) are seen, made for the entry into the head of odors and inhaled air. As previously stated, these are not straight passages open at both ends but oblique and winding, like the holes in sponges. Among the rest there is one on each side, however, that is straight at both ends and rather large; it is in a manner of speaking the first and nearest the front portion of the frontal bone, transmitting the vein 36 (G in figure 13, Book 7 and H in the figure in Chapter 14, Book 3) that extends to the hard membrane [dura mater] of the brain from the nasal cavity. Yet at the same time the other foramina would even seem straight and open at both ends if only the inner ossicles [labyrinthus ethmoidalis] placed in varying number at the top of the nostrils, noticeably porous and rather membraneous and cartilagineous, were removed.

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Whether these small foramina were also formed for the purpose of purging the brain of phlegm, we shall explain in the seventh book. But for the present I thought it should be added that phlegm is never filtered out through these except when the brain is full, 37 and that these foramina are blocked and other symptoms of a cold are brought on by the smallest amount of phlegm draining through them. 38 You should also be cautioned that foramina do not appear in this place with equal frequency in all skulls, just as the places [lamina et foramina cribrosa ossis ethmoidalis] (E in fig. 12, Bk. 7) where the olfactory organs [tractus et bulbus olfactorius] (D in the same fig.) are located are not observed in equal size in every case. 39 Moreover, the dog is the least phlegmy animal but is endowed with the most precise sense of smell; as it has the largest places for olfactory organs, so also many wide open foramina are seen in them facing forward and not down as in man.
K 3 , 4 Cavity [sinus frontalis] located between the two scales making up the frontal bone, 40 which many claim is the organ of smell because it contains air, which we have no doubt is marvelously necessary to smell. You will quickly observe how capacious this cavity actually is if you break the frontal bone in the region of the brows: it is very large and encloses a softish body 41 more or less corresponding to marrow, covered by a membrane. But it is all of such a type that you will find nothing resembling it in the entire body except in the numerous caverns and antra [sinus sphenoidales] (C and D in fig. 8, ch. 6) visible in the cuneiform bone. Except where the anterior plate of the frontal bone is eroded by the Gallic disease 42 or punctured by a wound, we see air driven from this cavity [sinus frontalis] with such force in expiration that it will instantly blow out a candle flame. For this cavity not only extends to the area of the brows and certain out-of-the-way foramina [ff. ethmoidalia] in the nasal cavity, but it also runs into that part [pars orbitalis ossis frontalis] of the frontal bone which has been stated makes up the upper region of the eye socket. 43
L 3 Foramen [lamina et foramina cribrosa ossis ethmoidalis], or rather fissure, of such a shape as the edge of a fingernail would make in wax; it is made to strengthen the hard membrane [dura mater] of the brain (beneath D in fig. 13, Bk. 7) at this point. No doubt it was necessary, not only here where it is perforated by many foramina but in numerous other places, that the hard membrane be attached to the brain and that it send fibers and vincula through the skull. You will also be able to observe that these fissures assist somewhat in bringing air into the brain if you judge by pushing an animal bristle into the cavity [sinus frontalis] of the frontal bone just mentioned and into the nasal cavity that they come to an end, 44 and if you notice besides that they extend 45 into the caverns [sinus sphenoidale] in the cuneiform bone.

Book One -- The things that sustain and support the entire body, and what braces and attaches them all. [the bones and the ligaments that interconnect them] | Chapter 12 On The Foramina of the Head and the Upper Maxilla