374 MARSUPIALS. 



in this as in all other Marsupials have two roots ; their crown 

 presents a simple compressed conical form, with a posterior tubercle 

 which is most developed on the hindmost. The true molars (mj in 

 the upper jaw are unequally triangular, the last being much smaller 

 than the rest ; the exterior part of the crown is raised into one 

 large pointed middle cusp and two lateral smaller cusps obscurely 

 developed ; a small strong obtuse cusp projects from the inner side 

 of the crown. The molars of the lower jaw are compressed, tri- 

 cuspidate, the middle cusp being the longest, especially in the two 

 last molars, which resemble closely the sectorial teeth {dents car- 

 nassi^res) of the dog and cat. 



The dental formula of the genus Dasyurus, is : 



Incisors — : canines — : premolars — ; molars — : == 42. 



3—3 ' 1—1 ' r 2—2 ' 4—4 



The eight incisors of the upper jaw are of the same length 

 and simple structure, and are arranged in a regular semicircle 

 without any medium interval. The six incisors of the lower jaw 

 are similarly arranged, but have thicker crowns than the upper 

 ones. The canines present the same or even a greater relative 

 development than in the Thylacine : in an extinct species of 

 Dasyurus {\) they had the same form and relative proportions as in 

 the Leopard. The spurious molars (p) have a pointed compressed 

 triangular crown with a rudimental tubercle at the anterior and pos- 

 terior part of its base. The grinding surface of the true molars (jn) 

 in the upper jaw is triangular ; the first presents four sharp cusps, the 

 second and third each five ; the fourth, which is the smallest, only 

 three. In the lower jaw the last molar is nearly of equal size with 

 the penultimate one, and is bristled with four cusps, the external one 

 being the longest : the second and third molars have five cusps, three 

 on the inner and two on the outer side ; the first molar has four cusps : 

 these are all sharply pointed in the young animal, in which the 

 posterior tubercle of the posterior molar in the lower jaw is divided 

 into two small cusps. 



The carnivorous character of the above dentition is most strongly 



(1) Dasyurus laniarius : the fossil remains of this species were discovered with those of 

 two gigantic species of Kangaroo in the bone-caves of Wellington Valley, by Major, now Lieut.- 

 Col. Sir ITiomas L. Mitchell. 



