Tertiary.-] PAL^iEONTOLOGY OF VICTORIA. {MammaHa. 



Plate XXI., Fig. 1. 



THYLACOLEO CARNIFEX (Ow.). 



[Genus THYLACOLEO (Ow.). (Sub-kmgdom Vertebrata. Class Mammalia. Order 

 Marsupiata. Fam. Paucideutata). 



g Q 1 1 o g I 1 



Gen. Char. — Dental formula : — i., ; c, ; p.m., : m., . First inci- 



1—1 '0 — 0''^ '3 — 3 '2 — 2 



sors, above and below, laniary, long, pointed, slightly arched, backward, compressed ; second and 

 tliird incisors abore much smaller and moderately compressed. Canines small, conical pointed. 

 Premolars, second and third above very small, simple ; fourth very large, compressed, carnassial 

 slightly arched, convex outside, concave inside ; below second and third very small rudimen- 

 tary, foiu-th very large, compressed, carnassial, arched like that above. Molars — above one 

 tubercular, set transversely to posterior inner end of the fourth premolar (j). 4) ; below first 

 molar bi-tubercular of moderate size, second molar very small, both in line with the carnassial 

 fourth premolar.] 



Description. — Maxillary teeth. — First laniary incisor, with a longitudinally 

 elliptical base, 11 lines in antero-posterior diameter, and 7 lines in transverse dia- 

 meter (leng-lh and form of ])oint imperfect), more convex on outer than on inner 

 side, anterior side convex (not exhibited), posterior side slig-htly concave ; cement 

 reaching- about 6 lines above base. Second incisor small, blunt, the outer face 

 divided by an oblique furrow extending backwards from near anterior basal portion 

 to near middle of inner worn edge of crown ; antero-posterior diameter 5 lines, 

 lateral diameter .5 lines, vertical length of crown 3^ lines on outer side, 5^ lines on 

 inner side. Third incisor large, compressed to a narrow straight cutting edge 4 

 lines long, outer face flattened, arched downwards and forwards and usually divided 

 by an impressed groove nearly from base to cutting edge a little in front of the 

 middle ; inner face with the anterior fourth forming a definite thickened vertical 

 ridge, the rest converging with slight convexity to a narrow posterior edge; antero- 

 posterior diameter of base 5J lines, transverse diameter in front 5 lines, depth frtm 

 base to cutting edge of outer enamelled snrfiice 7 lines. The three incisors form a 

 series on each side arching outwards and backwards from the front laniary one. The 

 next succeeding tooth, or canine, is situated at the inner side of the posterior end of 

 the third incisor, about 2J lines inside the outer surface of maxillary, and its socket 

 is crossed nearly in the middle by the premaxillo-maxillary suture, the base elliptical, 

 5 lines long and Si lines wide, crown conically pointed, much more convex on the 

 outer than on the inner face, anterior and posterior edges blunt, transverse diameter 

 at base rather less than the height of the ajiex of the conical crown. On the outer 

 side of the posterior third of the fourth tooth or canine is the 5th from the laniary 

 or the anterior small premolar, length and width of base of which are about 3^ 

 lines, and about three lines behind the hind edge of the third incisor. (The other 

 teeth in the upper jaw absent in our s])ecimen.) From anterior edge of first incisor 

 to posterior edge of fourth tooth 3 inches 3 lines. There is no interval between the 

 second and third incisors owing to the forwai-d inclination of the third tooth, but 

 there is a slight interval between the first and second. Lower jaw or mandible (the 

 single large laniary incisor broken oif in this specimen, but its root under front edge 

 of large premolnr (;?. 4) 11 lines in verticiil diameter, 6| lines in transverse dia- 

 meter); depth of ramus in front of carnassial 1 inch 9 lines, depth at hind edge of 

 second molar (?«. ?) 2 inches 3 lines; length from front of carnassial to hind edge 

 of second molar {m. 2) 2 inches C lines. The small functionless premolars {p. 2 

 and p. 3) are transversely or obliquely oval, and so approximated that it is diflicult to 

 determine whether they form one tooth or two, situated close to the inner side of 



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