Cope,] 322 (Dec. 7, 
premolar, and the second and third true molars. The fourth premolar has 
two external, and one internal cusps, and the true molars have four cusps 
each, The cusps are of peculiar form. The second true molar resembles 
a convex body which has been divided by two cuts at right angles to each 
other, from which the quarters thus produced have spread away from each 
other subequally. The external faces of the cusps are convex. The 
apices are acute. The last superior molar is larger anteroposteriorly than 
transversely. The fourth premolar (supposed) is two-rooted. 
These molar teeth remind one of the inferior molars of Ptilodus, through 
they differ much from them. The genus is probably nearer to Catopsalis, 
and belongs to the Marsupial order. The presence of only two series of 
cusps in the superior molars, distinguishes it from these genera, which 
have presumably three series of such cusps. Lemoine has shown this to 
be the case in WMeoplagiaulaa. 
Ohar. specif. The external cusps of the fourth premolar are flattened 
on the external side, and lean a littleinwards. The internal cusp (proba- 
bly homologically the anterior) is opposite the anterior external, and 
has a convex internal face. Its apex is acute and compressed ; the apices 
of the external cusps are trihedral and acute. 
The cusps of the second true molars are more widely separated trans- 
versely than anteroposteriorly ; that is, the longitudinal fissure is wider 
than the transverse. The apices are all acute, the internal trihedral, the 
external more compressed. 
The transverse diameter of the last. true molar is smaller than that of 
the second true molar, while the longitudinal is nearly the same. The 
crown projects convexly posterior to the posterior pair, and there is a small 
tubercle at the anterior base of the external anterior cusp. 
None of the teeth preserved display cingula. The bases of the crown 
are smooth, but the cusps are sharply and finely parallel-grooved on their 
external faces. 
Measurements. M. 
: i) COMUOLODORTOTION.. iisioetuleveys es) .O0B0 
Diameters of P-m. iv { ULAMSVOTROUG iil dee ces havuwed 0088 
F ve GC MMLCTOPORUCTION ss sibleie Welds da moede MOBO 
Diameters of m. if j TONS VOLEC ss 650+ ebialevuss dileiebin » 1 MOUBD: 
, we» ¢ anteroposterior...... bolas Hate KOOOD 
Diameters of m. tii TOE V OTRO 6 ieiebiy ganiviire we vinyls UOBU 
D. Baldwin, discoverer. 
CATOPSALIS FISSIDENS, Sp. NOV. 
This Marsupial is represented by a portion of the lower jaw which sup- 
ports the molar teeth. The first, which is probably the fourth premolar, is 
represented only by its single root, which fills a round alveolus near the 
antérior base of the first true molar. 
In size this species is intermediate between the small 0. folatus and the 
large O. polluw, The first molar is the longer and narrower, and the 
