64 ] 
RECORDS OF W.A. MUSEUM. 
Sthenurus, Owen (1873).! 
Sthenurus atlas, Owen (1838). 2 
Macropiis atlas, Owen .. .. Mitchell's “ Three Expeditions into the 
Interior of Eastern Australia,” 2nd 
Ed., Vol. II., p. 359, 1838. 
Protemnodon anak, Owen (in parte) .. Phil. Trans., 1874, p. 275. 
STHENURUS ATLAS. 
There are several specimens which have been identified as 
belonging to this species. 
A small fragment consisting of the anterior portion of the left 
ramus with the root of the incisor, the diastema, and the permanent 
premolar rising from its alveolus, has this important tooth in perfect 
condition. The tooth closely resembles the rising premolar figured 
by Prof. Owen on Plate xxii. (figs. 5 and 6) in the Philosophical 
Transactions of 1874, has a somewhat different tooth sculpture, 
suggesting that this feature is subject to a certain amount of 
variation (see also Owen’s various figures of this premolar). The 
size of the diastema, the dimensions of the mandible, and the 
position of the predental foramen agree exactly with Owen’s 
drawings. 
The differences between the lower permanent premolar of this 
species and the corresponding tooth of 5 . occidentalis have been fully 
discussed,^ but are more readily discernible when specimens of the 
two species are placed side by side. 
Another example (in three fragments) comprises the major 
portion of the right horizontal ramus, with the base of the coronoid, 
the extent of the cheek teeth, part of the diastema, and the perfect 
incisor. The first and second molars, both much worn, are the 
only perfect cheek teeth present. The longitudinal links have 
disappeared, and the crown of the tooth is practically reduced to a 
flat grinding surface ; there is no trace of any verticle grooving or 
folding. A portion of the outer surface of the permanent prernolar 
is preserved, the other teeth are represented by roots only. The 
1 For synonymy of the genus, vide ante, p. 31. 
3 In Mitchell's "Three Expeditions,” 2nd Ed., p. 359, 1838. 
3 Vide ante, pp. 32, 33 and 34. 
