XIII 



PHYLUM CHORDATA 



491 



this bone, the tympanic being always small, and never ankylosed 

 to neighbouring bones. The internal carotid artery perforates the 



nag 



p. ma x ^^ : -^^^' 



x^2 



Icr- fr J { 



ma.sc 



^ 

 'r 



A^VH^ 1 



8.0 C 



oc.CO* 



wet* 



par.oc 



FIG. 1063. Skull of Dasyurus (lateral view), al.sph. alisphenoid ; any. angular process of 

 mandible; /r. frontal; ju. jugal ; Icr. lacrymal ; max. maxilla; nas. nasal; oc. cond. occipital 

 condyle ; orb.sph. orbitosphenoid ; par. parietal ; par.oc. paroccipital process; p.max. pre- 

 maxilla ; s.oc. supra-occipital ; /. squamosal ; #/. zygomatic process of squamosal. 



eac.oc 



bas.oc 



FK;. 1004. Skull of Bock Wallaby (Petrogale penicillata) (ventral view). Letters as in 

 Fig. 1063, except all. alisphenoid. In addition, IMS.OC. basi-occipital ; bas.sph. basi-sphenoi ; 

 i-x.oc. ex-occipital ; pal. palatine ; pt. pterygoid ; ty. tympanic. 



basi-sphenoid. The optic foramen is not separate from the 

 sphenoidal fissure. In all except Tarsipes the angle of the 



