. Outlines of zoology. g membrane andnot preformed in cartilage. (The names of the membranebones are printed in italics.) We have already noticed the chief characteristics of themammalian skull, such as the usual persistence of sutures, the two condyles, the bonypalate, the fusion of theperiotic bones, the articu-lation of the mandible withthe squamosal, the fusionof the parts of each ramusof themandibleintoa singlebone in the adult, and thethree ossicles of the ear. The foramen magnum isbounded by the basioccipitalbeneath, the exoccipitals on thesides, the supraoccipital exoccipital
. Outlines of zoology. g membrane andnot preformed in cartilage. (The names of the membranebones are printed in italics.) We have already noticed the chief characteristics of themammalian skull, such as the usual persistence of sutures, the two condyles, the bonypalate, the fusion of theperiotic bones, the articu-lation of the mandible withthe squamosal, the fusionof the parts of each ramusof themandibleintoa singlebone in the adult, and thethree ossicles of the ear. The foramen magnum isbounded by the basioccipitalbeneath, the exoccipitals on thesides, the supraoccipital exoccipitals form most ofthe occipital condyles, but basioccipital contributes a smallpart. In many Mammals theexoccipitals alone form the con-dyles. From each exoccipital aparoccipital process descends,and is applied to the tympanicbulla—a dilatation at the baseof the tympanic bone which pro-tects the external auditory the roof of the skulllie the supraoccipital, the inter-parietal, Vne parielals, ihefrcni-. Fig. 384.—Upper surface ofrabbits skull. .(V.,Anterlornostril;/;i/A.,premaxilla;iV/4., C , i =!??nasal; FR., anterior part of frontal; MX., *^> ^^d the part of maxilla; /., anterior part On the very front of the skull ofjugal; m^., supraorbital process of fton-are the firemaxilla, bearing thetal, FRR., part of frontal; // ^^^^^^ (^^^^^^ - ? ? - -^ ? posterior end of jugal protruding below zygo- Behind each/;-«- matic portion of squamosal (); P.^., ^?^^^ is a maxilla, bearingparietal; AM., external auditory meatus; the premolars and molars; be- f^amS°°*^^°™°^^ ^?^ ^ ^^S ^^ zygomatic or teuiporal arch projecting be-neath the orbit, is the Jugal or malar, which unites posteriorly withthe squamosal. This zygomatic arch bridges over the deep temporalfossa behind the orbit, and serves for the insertion of muscles, and its squamoso-maxillary structure occurs outside of Mammalia in the SKELETON. 703 Anomodont reptiles only. The
Size: 1228px × 2035px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookidcu3192, booksubjectzoology
