Comparison of the skulls of : a - Nemegtosaurus mongoliensis n. sp., b - Diplodocus longus MARSH (after MARSH, 1878), c: - Dicraeosaurus hansemanni JANENSCH (after JANENSCH, 1935/36) , d - Antarctosaurus wichmanianus HUENE (after HUENE, 1956). Abbreviations: An - angular, Apf - accesory preorbital foramen, Avpp - anteroventral process of the pterygoid, Bo - basioccipital, D - dentary, En - external naris, Fr - frontal, Inf - infraorbital foramina, Itf - infratemporal fenestra, J - jugal, L - lacrimal, Mv - mandibular vacuity, Mx - maxilla, Na - nasal , Op - opisthootic, Or - orbit, Par - parietal, Pmx - premaxilla, Po - postorbital, Porf - preorbital foramen , Prf - prefrontal, Q- quadrate, Qj - quadratojugal, Sa - surangular, Soc - supraoccipital, Sq - squamosal, Stf - supratemporal fossa |