. Outlines of zoology. asphenoid). This bone gives off two stout processes,the basipterygoid processes, which articulate with the pterygoids. Eachpterygoid is connected posteriorly with the quadrate bone of the corre-sponding side, and anteriorly with the palatine. From the union ofpterygoid and palatine, a stout os transversum or transpalatine extendsoutwards to the maxilla. In front of the palatines lie the small vomers,which, in their turn, articulate with the premaxilla and maxilla, both of 624 REPTILIA. which are furnished with small pointed teeth. In the posterior regionof the skull we h
. Outlines of zoology. asphenoid). This bone gives off two stout processes,the basipterygoid processes, which articulate with the pterygoids. Eachpterygoid is connected posteriorly with the quadrate bone of the corre-sponding side, and anteriorly with the palatine. From the union ofpterygoid and palatine, a stout os transversum or transpalatine extendsoutwards to the maxilla. In front of the palatines lie the small vomers,which, in their turn, articulate with the premaxilla and maxilla, both of 624 REPTILIA. which are furnished with small pointed teeth. In the posterior regionof the skull we have still to notice the large ex-occipitals with which theopisthotics are fused, and which are continued into the conspicuousparotic processes. The lateral walls of the brain-case are largely formedby the paired pro-otics. Internally, an important bone, the epipterygoidor columella (not to be confounded with the columella or stapes ofthe ear), extends from the pro-otic to the pterygoid. The orbit is \ps >. Fig. 341.—Side view of skull oi Lacerta,—After W. K. Parker. px.^ Premaxilla; vtx., maxilla; /., lachrymal; y., jugal; ^transpalatine; epg.^ epipterygoid;/^., pterygoid; bpg.^ basi-pterygoid; ^o., basioccipital; y., (Quadrate; occ, occipitalcondyle ; squamosal ,? ^ pro-otic : ^ postorbital; j/.i,j/.2j_ supratemporals ; ps.^ presphenoid (the optic nerve is seenissuing in front of the end of the reference line); /.«., mes-ethmoid ; ,^ supraorbitals ; pf.^ prefrontal;, «., nasal; ar.^articular ; ag., angular ; sag.^ surangular ; cr., coronary ; d.^dentary. bounded posteriorly and inferiorly by the jugals. There is no ossifiedquadrato-jugal, and thus the lateral temporal fossa is open below in thedried skull (contrast Hatteria). The other fossae of the dried skull arethe supra-temporal on the upper surface, and the posterior-temporal onthe posterior surface. Each half of the lower jaw is composed of six bones, which use inthe adult. The
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Keywords: ., bookcentury1900, bookdecade1910, bookidcu3192, booksubjectzoology
