100 
(C. vera Winge). With respect to fossil forms it may often be 
doubtful which of these three orders they must be referred to, on 
which account it would be of special interest if one could find 
Characteristic distinctive features in the teeth of either of them. 
The upper carnassial type is well known: The .outer cutting 
edge (blade) formed by two longitudinal crests, (the anterior one 
generally with a high pointed cusp and separated from the posterior 
more horizontal one by a notch), is supported by two roots; in front 
of the anterior cusp are generally one or a couple of small cusps, 
and on its inner side is in most cases placed a more or less heel- 
like tubercle supported by a special root. According to Osborn's 
nomenclature they are generally named pr., pa., me. and ps. 
The cusp-homologies of the carnassial of Sarcophilus ursinus 
(m?) are not difficult to understand when compared with m! and 
this tooth again with the molars of Dasyurus. (Fig. 1, vide also 
the diagrams on pag. 108). In the 
latter genus we find in the upper 
molars the exterior edge composed of 
three small cusps (1-2-3 of Winge); 
inside them, and connected with them 
by crests, are two high cusps, 4 and 5, 
inside them again one, 6. (Diagram 1). 
The same six cusps are very easily 
recognised in m! of Sarcophilus, where 
5 is greatly enlarged and about to 
engulf 2 and 3, whereas 4 is small and on the same level as 1. 
The catastrophe has fallen on m?: 2 has been totally swallowed 
up by 5, and 3 appears to be a mere appendix to its hind end, 
1 and 4 are placed beside one another as two equal cusps. (diagr. 2)- 
The characteristic is the equivalence of 1 and 4 and the predomi- 
mance of 5, With Thylacinus the same is the case, but the single 
stages in development are more veiled because of the sharper cha- 
racter of the tooth (diagr. 3). 
In Carnivora primitiva we find generally both m! and m? 
Fig. 1. Sarcophilus ursinus. 
am”, 
