History of Monsters, Page 79

also so that the muscles, if it were entirely made of flesh, would not collapse and compress the heart and lungs.

Beginning with the head—the seat of all senses according to the opinions of Galen and Avicenna—we determine its parts to be the hair, skin, flesh, pericranium, skull, the thick and thin membranes (namely the dura and pia mater), the brain with its three ventricles, the *rete mirabile*, and the basilar bone. Following Galen’s view, the skull consists of seven bones joined by sutures; nature did not craft it as a single continuous bone so that waste matter could be more easily expelled through these seams. Nevertheless, human skulls are occasionally found without sutures. Hesiod, for instance, recounts that after the slaughter at Plataea, the head of a Persian was found without any structure of sutures. Similarly, Caelius Rhodiginus records that the heads of Ethiopians are not loosened by any seams, and Aristotle himself admits to having seen a human skull entirely devoid of sutures.

Once the skull is removed, two membranes—the thick and the thin—appear. When these are lifted, one observes a volume of brain matter far greater than that found in any other animal of similar size. The brain is divided into two parts, anterior and posterior; the anterior portion is split in two by an intersecting membrane which anatomists call the "reaping sickle" (*falx*) due to its shape. Beneath the brain lie three ventricles where the "animal spirits" are generated, and where one can also see a substance mimicking the form of a worm. Near the front of the lifted brain, one can see small fleshy growths very similar to nipples; these are called the mammillary processes, through which the sense of smell is achieved. There also appear two large nerves called the optic nerves, which originate in the brain and reach the eyes. If the brain is lifted further, a second pair of slender nerves appears, which enter the eyes to facilitate voluntary movement. A third pair extends to the parts of the face, while a fourth pair—along with a portion of the third—descends into the middle belly. From these arise the recurrent nerves specifically responsible for the voice. A fifth pair heads to the petrous bone at the root of the ear. A sixth pair of slender nerves extends to the palate for the sense of taste, and a seventh pair serves the tongue.

With the brain entirely removed, two lower membranes and the basilar bone come into view. This bone, the hardest of all, is called the base and foundation of the brain and head; it is divided into the petrous bones of the nose, two lateral bones, and the bones of the eyes. Within the eye, one may examine the muscles, seven tunics, and three humors: the aqueous, crystalline, and vitreous. The ears are located on each side of the head so that sound may be perceived from both directions, their cartilaginous outer parts having been crafted for protection. The cavity of the ear is covered by a thin membrane woven from the fibers of the auditory nerves, called the *tympanum* or eardrum. Slightly lower down, the teeth present themselves for consideration; they are so named because the Greeks call them *odontes*. Their number varies, as more are seen in men and fewer in women; indeed, in some men thirty are found, while in others only twenty-eight are observed. Not all teeth are of the same shape: the front ones, suited for cutting, are called incisors; the next are the canines, shaped like the teeth of dogs, with two guarding the right side and two the left; the rest are called molars, for they grind the food already cut and broken by the incisors.

We now descend to the middle belly—the thorax—which is contained between the diaphragm above and the "little fork" (*furcula*) below. Some call this part the *pectus* (chest), as if it were made of "compacted" ribs, or perhaps from *pecten* (a comb), as these bones mimic a comb's shape. The bones making up this region consist of twenty-four ribs and seven sternal bones; when the two "forks" known as clavicles are added, the total comes to thirty-three bones. It should be noted in passing that the number of ribs sometimes varies; for instance, Schenck mentions a woman who was equipped with twenty-five ribs. Furthermore, in a public dissection in the year 1525, Jacopo Berengario da Carpi saw a true double rib where it joined the bones of the chest. Between the twelve ribs on each side lie eleven spaces containing twenty-two intercostal muscles, called *mesopleurioi* by the Greeks. In addition to these and the diaphragm, two muscles are observed in the upper part and two in the lower, along with three muscles of the neck, seven of the back, and eight of the lower belly, bringing the total count to forty-four.