268 MARSUPIALIA. 



are four grinders on each side ; the two middle are the largest, the last 

 the least : their base is a triangle, having one angle obtuse and two 

 acute. Their base is composed of two surfaces, an inner and an outer, 

 divided by processes or points ; it is the inner that the grinders of the 

 lower jaw oppose when the mouth is regularly shut. The lower jaw 

 has three fore -teeth or incisors on each side, the first considerably the 

 largest, projecting obliquely forwards; the other two of the same 

 kind, but smaller ; the last the smallest. The holder in this jaw is not 

 so large as in the upper jaw, and is close to the incisor : there are three 

 cuspidati, the middle one the largest, the last the least. They are 

 cones standing on the base, but not on its middle, rather on its anterior 

 side. There are four grinders ; the two middle are the largest, rather 

 quadrangular ; each has a high point or cone and a smaller one on the 

 outer edge, and three smaller points on the inner edge. 



It is impossible to say critically what the various forms of these 

 teeth are adapted for, till we have the general principles of teeth. In 

 the front we have what may divide and tear off; behind those we have 

 holders or destroyers ; behind these, such as will assist in mashing, as 

 the grinders or carnivorous teeth of the Hon (sectorial or camassial 

 teeth) ; last of all, there are grinders to divide parts into smaller por- 

 tions, as in the graminivorous ; and the articulation of the jaw in some 

 degree admits of all these actions \ 



1 [A comparison of the foregoing description with the jaws and teeth of a Phas- 

 cogale (see No. 1884, Osteological Series, Mus. Coll. Chir.), cannot fail to impress 

 the comparer with Hunter's faculties of accurate and minute description. It was 

 probably without parallel at the time when it appeared in print (White's Journal, 

 &c., 1790, p. 281). The nature of the teeth, as now understood and admitted, is 

 shown by the formula : — 



.4—4 ] — 1 3—3 4—4 4a 



2 a = 3; c 1 ~^3-=i' w I=4= 46 - 

 Hunter's ' second class of incisors' have been called the ' lateral incisors' by Mr. 

 Waterhouse (Nat. Hist, of Mammalia, 8vo, 1845, p. 404) : Hunter notices that 

 " the two front incisors of the upper jaw are longer," and Mr. Waterhouse remarks 

 that Phascogale penicillata differs from some other species "in having the foremost 

 of the three lateral incisors of the upper jaw the largest" (ib.); the number of the 

 paremolars, termed 'cuspidati' by Hunter, from their shape, shows that the 

 ' Tapao Tafa ' was a Phascogale, not a Dasyurus, in which genus the premolars are 



^- instead of -^-. It was, however, referred by Geoffroy St. Hilaire to his genus 



Dasyurus ; but Temminck regarded the Dasyurus Tafa, Geoff, as a doubtful species, 

 remarking " elle n'a point 6t6 vu depuis par aucun naturaliste :" and Lesson sus- 

 pects it to be founded on the immature state of the spotted dasyure {Dasyurus 

 viverrimus, Geoff). The hinder half of the body of the tapao tafa, described by 

 Hunter, is preserved in Phys. Series, No. 3758, to show the marsupium and teats, 

 which are eight in number, arranged in a circle; the tail is that of the Phascogale 

 penicillata of Temminck. The dentition is adapted, like that of Diclelphis, for such 

 food as Hunter found in the stomach of the small opossum described at p. 266.] 



