Ill 



Tribe CARPOPIIAOA. 

 Genus Pktucolarrtot. 



1644. The skull of the Kuala (PkaecolarctotfiHctui). 



It is remarkable for the uniutuJ length of the exoccipital processes, the short mattoid* 

 butting against the outer side of their base. The sphenoidal Imllir are excessively devr- 

 lojx-d. A bristle is pasted through the left ranali* earoiint, in the side of the basiflphrnoiil, 

 nd part of the calrarium is removed, showing the entry of the eanal into thr shallow sella 

 turcira. The petronal is impressed by a deep cerebellar pit. The base of the lygomatic pro- 

 cess fa *r a r*r l hy an air-cvll communinitiiig with the tympanum, and is perforated by 

 venous canal. The zygomatic arches are long and strong : the pterygoids are distinct deep 

 plates. The lacrymal foramen is extraorbital. The angle of the jaw is bent upwards and 

 very slightly inwards. 



Dental formula : i ^, e , p |, m j^= 3D. The true molars are larger in propor- 

 tion than in the 1'halaugers ; each is besrt with four three-sided pyramids, the rus|>* of which 

 wear down in age, the outer series in the upper teeth being the first to give way , thow of 

 the lower jaw are narrower than those of the upper. Thr spurious molar* are compressed, 

 and terminate in a rutting edge ; in those of thr npprr jaw thrrr is a small parallel ridge along 

 the inner side of the base. The canines slightly exceed in size the posterior incisors . thev 

 terminate in an oblique cutting edge rather than a point , thrir fang is closed at the extre- 

 mity ;* they are situated, a* in the I'halangrrs, close to the intermaxillary suture. The late- 

 ral incisors of the upper jaw are small and obtuse ; the two anterior or middle incisor* are 

 twice as long, broad and thick as the posterior incisors ; they are conical, slightly curved, 

 uncompressed, bevelled off obliquely to an anterior cutting edge, but differing essentially from 

 the drntet teatprarii of the RoJentia, in being closed at thr extremity of the fang. The two 

 incisors of the lower jaw resemble those of the upper, but are larger and more compressed ; 

 they are also formed by a temporary pulp, and its absorption is accompanied by a closure of 

 the aperture of the pulp-cavity, as in the upper incisors. The Koala, therefore, in regard to 

 the number, kind, and conformation of its treth, closely resembles the Phalaiigrrs, with which 

 it also agrees in its long neoutn and the general conformation of its digestive organs. 



Pmetnl hy Sir Ecerard Home, Bart., I'.P.R.S. 



1845. The skull of a young Koala (Pha#colarctosfuciui). 



In this Marsupial the permanent premolar comes into place before either the thin! or tin 

 fourth true molars have cut the gum : the canine* are just appearing. The tympanic bone 

 i* removed from the right aide. 



Presented by Sir Krerard Home, Bart., V.P.R.S. 



1846. The disarticulated bones of the head of a young Koala (Phcocolarctot futctui). 



The state of the dentition corresponds with that of the precediag specimen. The bones 



