17G 
ON 
SOMK NKW AND LITTLE KNOWN CREODONTS. 
, , 11 „,i nnitP ^troii.'lv divergent; the paroccipitnl processes are short and 
1«L t le occiput and is about as broad as in the dog; fte process is almost obso- 
l’r,md is hardly at all in advance of the condyles. The region of the cmnium behind 
the iwst-glciioids is exceedingly short compared with the same part m the Carnivora, 
the Lme is true of some other creodonts (e. g. Uemny.) as well as of the carnivorous 
marsupials and the insectivores. , , , -ji e 
The basi-sphenoid is very long; posteriorly it is broad but narrows rapidly for- 
wards- the alisphenoids are large and form eonsiderable part of the side waUs of the 
cranium; near the anterior edge is a strong overhanging ridge which runs obliquely 
forwards and upwards, and is continued on the frontal to the post-orbital process; the 
pterygoid plates are large and in all the species closely approximated; in H. lepto 
ccphalm they are actually united suturally, thus concealing the pterygoids and 
bringing the posterior nares very far back. The parietals are long but not very broad 
iKines and do not extend very far down on the sides of the cranium; this extension is 
least in H. horrid^is, somewhat greater in H. crtientus and still more so in H. crucians 
and Jl. leptocephalm. In front of the squamosal the parietal sends down a process 
to meet the alisphenoid; the sagittal crest is not strongly developed except posteriorly. 
The s(piamosals are large, extending well up on the side of the cranium and back to 
the crest of the inion; they vary in size in the different species, of course inversely as 
the extension of the parietals, as given above; the zygomatic process is heavy and 
dirt-ctcHl outwards and then curves forwards; the glenoid cavity is broad and concave 
in l)oth directions; the post-glenoid process is shaped much as in the dogs, but is con- 
tinueil as a low ridge the entire width of the cavity; this ridge is least marked in H. 
leptfx'ephalus; no preglenoid ridge is present. 
I'he pre-sphenoid is narrow and but little exposed, as the vomer conceals it. The 
limits of the orbito-sphenoids are not easy to make out, but they are obviously very 
small. 'fhe Irontals, on the other hand, are exceedingly large. In H. cruentus and 
II. horridus the cnmial constriction occurs at the fronto-parietal suture, in advance 
of this the frontals expand rapidly and inclose large frontal sinuses; in the smaller 
species the con.striction is just behind the orbit and the sinuses smaller. Prominent 
post-orbital processes are present, and as in Thylacynus, the nasal processes extend 
much in advance of the orbits. 
The mes-ethmoid is exceedingly large, even more so than in the carnivorous mar- 
supials; its size is most marked in the vertical direction, owing to the great height of 
the nasjil chamber. The vomer is long and high. The ethmo-turbinals are well 
dcvclo])cd and complexly folded, but none of the specimens I have examined enable 
m<‘ to state the condition of the maxillo-turbinals. The nasals are long, broad and 
archcnl from side to side; posteriorly they are wedged in between the frontals and 
reach their greatest breadth at the fronto-maxillary suture; the free ends are emar- 
