The comparative anatomy of the domesticated animals / by A. Chauveau ; second edition, revised and enlarged, with the co-operation of S. Arloing.

  • Fleming George, 1833-1901.
Date:
1873
Catalogue details

Licence: Public Domain Mark

Credit: The comparative anatomy of the domesticated animals / by A. Chauveau ; second edition, revised and enlarged, with the co-operation of S. Arloing. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    laclirymal, and temporal bones. It is described as having two faces, two borders, a base, and a smimlt. Faces.—Tho external face comin-ises two portions separated from each otber by a semicircular ledge that extends from the summit to the middle of the anterior border of the bone, and concurs to form the outer margin of the orbit. Tho anterior portion, smooth and concave, belongs to tho orbital cavity. The posterior, more extensive, is also smooth and slightly convex. The inter7ial face is excavated in its central part, which corresponds to the maxillary sinus. On its margin it shows dentations and lamellsB for articu- lation witb the supermaxillary bone. Borders.—Tho anterior, thin and denticulated, is joined to the lachrymal bone. The posterior, or masseterin border, is thicker, and constitutes a roughened crest, tbe zygomatic ridge, wbicb is continued above with the posterior border of the process of tbe same name, and below with the maxillary spine.^ Base and summit.—The hase, very thin, is united to the supermaxiiiary bone. The summit, flattened from before to behind and bevelled on its anterior face, joins the zygomatic process, and forms with it the jugal bridge or zygomatic arch. . . Structure and development.—This bone is rather spongy m its upper part, and is developed from a single nucleus of ossification, 6. Lachrymal Bone. A small, thin, and very liglit bone, bent on itself at a right angle it is situ- ated beneath the orbit, which it aids in forming, and is wedged between the frontal, nasal, supermaxillary, and zygomatic bones. It is studied on its external and internal faces and circumference. _ _ . . • Faces—The external is divided into two regions, superior and inferior by a curved crest which forms part of the orbital margin, and is provided ^dtb notches, wbicb are variable in their form and number. The superior region, named tbe orbital, because of its situation m the orbit, is sLghtly concave and smooth. It presents, near the orbital margin, the onfice of the lachrymal duct, wMch traverses the maxillary sinus and opens on t^^^ interna^ face of the supermaxillary bone, where it is continued by a fissure bebmd this is the lachrymal fossa. The inferior ov facial region is slightly bulging, and provided sometimes with a tubercle of insertion the lachrymal tubercle The internal face is employed, for the whole of its extent, in the formation of the walls of the maxillary and frontal sinuses; it exbibits a cylmdi-ical prominence produced by the bony tube of the lachrymal duct. Circumference.—This is very ii-regular and denticulated to respond to the neighbouring bones. ■ ^- ^ * i Structure and development.-This bono is entirely compact, and is developed from a single nucleus of ossification. 7. Nasal Bones. Situated on tbe anterior aspect of tbe head, these bones articuhite with each otberin the median line, and are fixed between the frontal, lachrymal, and supermaxillary bones; they are triangular in shape, e ungated from aW to bdow, flattened from before to beliind, and ofter for study tm faces, Unn borders a base, and a summit. ., , , F^cl-Tho external or anterior face, larger above than below, is convex > Tho designation of zyrjomatio crest is often given to these three parts ccUectively.