238 



MAMMALIAN ANATOMY 



mission of the auricular branch of the tenth cranial nerve ; it com- 

 municates with the tympanum by a small chorda tympani opening in 

 its anterior wall, and with the fossa for the stapedius muscle. 



Nomenclature. This bone is called the temporal bone, os tern- 

 porale, os temporis, or os temporum, from tempus, time, because of its 

 situation on the side of the head, where gray hairs usually first appear 

 " to mark the flight of time." It has also been known as os parietale 

 inferior, os lapidosum, the stony bone, os squamosum, and os crota- 

 phicum, from the Greek meaning the temple. The German word is 

 das Schlafenbein ; the French, le temporal. 



The squamous portion is also known as the squamosal, pars squa- 

 mosa, or the squama. In German it is called die Schuppe ; in French, 

 Vecaille, or la portion ecailleuse. 



FIG. 174. 



Apex of Petrous. -/Z 



Ectotympanic Hook. 



Cavity for Small 

 Whorls of Cochlea.. 



First Whorl of Coch- 

 lea. 



Spiral Cribriform 

 Tract. 



Superior Cribriform Spot. 



Middle Cribriform S/mt. 



Superior Rim of Auditory 



Meatus. 



Foramen Singulare. 

 Superior and Posterior \-~~~ 

 Semicircular Canals, j 



Posterior Semicircular Canal. - ~~ 



Pit for Long Process of Malleus. 

 ...Fossafor TENSOR TYMPANI. 



r .-Fencstra Oval is. 



...Slit for Tendon of STAPEDIUS. 

 Bridge. 



..Superior Semicircular Canal. 

 External Semicircular Canal. 



-Roof of Vestibule. 



External Semicircular Canal, 

 for STAPEDIUS. 



TRANSVERSE LONGITUDINAL SECTION THROUGH LEFT TEMPORAL. INFERIOR ASPECT. 



(Enlarged Four Times.) 



The petrous portion is also known as the petrosal, os petrosum, pars 

 petrosa ; in German as das Felsenbein ; in French as le rocher. The 

 mass formed by the union of the petrous with the mastoid is termed 

 the petro-mastoid, the petrosal, or, because it encloses the internal 

 ear, the periotic. 



The mastoid is also known as pars mastoidea, die Warzenpartie, la 

 portion masto'idienne. 



The tympanic portion is also known as the tympanic plate and 



