202 DE. EMBLETOX AND ME. ATTHEY OK THE 



directed backwards from the under surface of the bone, and 

 marked by muscular impressions. 



The squamous lones, of an irregular shape, lie external to the 

 parietal, and form the anterior curved margins of the temporal 

 fossae, having the postorbital and the supratemporal, Huxley, 

 the tympanic, Von Meyer, on their outer side. They are con- 

 nected in front with the postfrontal and postorbital, and behind 

 with the mastoids. By a small posterior part of their inner 

 margins they are sutured to the so-called " supraoccipitals." 



The postorbitals are of a somewhat rhomboidal outline ; their 

 anterior internal borders, concave, form the posterior and exter- 

 nal margins of the true orbits; their inner angles, which are 

 truncated, abut upon the postfrontals, which bound the orbits 

 posteriorly and internally. These two bones, the postorbital and 

 postfrontal, with a small portion of the posterior end of the 

 prefrontal, form the whole of the bony margin of the true orbit. 

 The anterior angles of the postorbitals project into the orbital 

 vacuities, marking on their outer margins the boundary of the 

 true orbit, as noticed already under the heading ' l orbital vacui- 

 ties" The postorbitals articulate by their inner and posterior 

 sides with the squamous, and by their outer and posterior with 

 the supratemporal of Huxley, the tympanic of Yon Meyer. Their 

 remaining sides, the anterior and the external, join with the 

 jugal bones. 



The malar s or jugals are much elongated, and form the middle 

 two-thirds of the external borders of the orbital vacuities (on the 

 right side the bone, as already noticed, has been partially dislo- 

 cated), and overlap by their external borders nearly six inches 

 of the borders of the maxillaries : they grow narrower as they 

 extend forward, and have a pointed end received into the angle 

 formed by the diverging posterior edges of the maxillaries and 

 lacrymals; extending backwards they become rapidly broader, 

 and cease posteriorly in an obliquely running zigzag line of 

 suture, which unites them, from within outwards, to the post- 

 orbitals, the supratemporals, and the quadrate jugals. The ex- 

 ternal borders of this upper surface of the maxillary part of the 

 cranium are formed largely by these bones, and are completed 



