PLATE XIII. 
Piig(^ 
Palceomastodon (?) headnelli, Andrews ; anterior portion of young skull, upper 
and (1 a) side views : tliree-fonrths nat. size; also (I b) crown view of left 
upper teeth : nat. size. 
Flnvio-marine beds (Upper Eocene). [C. 8116.] 138 
do.f., antorbital foramen. 
/'/•., frontal, 
i., incisor. 
ja., jugal. 
lac., lachrymal. 
mcs.(f., mesethmoid groove. 
iiutt. 2-4, milk-molars. 
vix., maxilla. 
na., nasal. 
nat\, external nares. 
orb., orbit. 
pal., palate. 
pmx., premaxilla. 
~U9-i zygomatic process of maxilla. 
