32 ] 
RECORDS OF W.A. MUSEUM. 
Cheek Teeth. Length of entire series (in situ) from anterior 
edge of P4 to hind edge of M4 60 to 6imm., Mi to M4 44.5mm., 
Mi to M3 32.5mm. 
Premolar (P4), antero-posterior dimension 17mm., summit of 
crown 12.5mm., greatest width of anterior moiety 7mm., of 
posterior gmm. 
First Molar (Mi)i, length 10.5mm., fore lobe 8.5mm., hind 
lobe 8.5mm. 
Second Molar (M2), length 11.5mm., fore lobe 8.5mm., hind 
lobe 9.5mm. 
Third Molar (M3), length 12.5mm., fore lobe lomm., hind 
lobe lomm. 
Fourth Molar (M4), length 11.5mm., fore lobe 9.5mm., hind 
lobe 9mm. 
The Mandihle, greatest length of jaw i6omm. (from the tip 
of the incisor to the hind margin of the coronoid) ; greatest depth in 
front of P4, 34mm. ; greatest depth at M4, 35mm. ; depth behind 
P4, 31mm. Thickness under P4, 15mm.; behind M3, i7-i8mm. 
Dental vascular foramen to 8mm. below the edge of diastema, 
slightly in advance of P4. A second smaller foramen below the 
base of posterior lobe of Mi. 
Description of the Specimen. 
The incisor much resembles the corresponding tooth of the 
S. atlas figured by Owen (Phil. Trans. 1874, pi. xxii., figs. 5 and 6), 
but has a relatively longer working surface, possibly on account of 
the greater age of the individual, and is more erect. 
The premolar is elongately oval in horizontal section, possess- 
ing a marked constriction at a point 7mm. from the anterior basal 
edges, particularly on the outer aspect, which almost divides the 
tooth into a fore and a hind lobe ; the oblique horizontal continua- 
tion of this vertical groove, inwards and backwards, gives a 
transversely bilobed appearance to the hinder part of the crown, 
and causes the lobe that represents the anterior portion of the outer 
aspect to form the whole of the inner surface. The posterior 
1 This tooth corresponds to the D4 of Prof. Owen. The Mi of this authority 
agrees with the M2 of later authorities. In this table of measurements the width 
of the lobes of the molars is the extent of the cutting edges of the lobes. 
