(aT Tee ee F 
Rp EA ea Pe aes ee EN 
Ee ee E E T ee Pe eee ee ee VTE 


1891.] Cretaceous Mammata. 601 
would probably be found to coincide similarly with the type 
of Cimolomys bellus, unfortunately not figured by the author. This 
gives us the characters of the molars of what was possibly a 
new genus (Cimolomys) of the Plagiaulacide, intermediate between 
Plagiaulax with three well-developed premolars, and Ptilodus with 
one large and one ex- 
tremely small premolar. 
This genus cannot at 
present be defined, be- 
cause, so far as we can 
compare the molars and 
premolars, they closely 
resemble in size and de- 
G. 3.—Upper and lower molars of Cimolomys. velopment the corres- 
(Cimoiomids, a, „Cimolomys are ilis. (Cimolo- = 
dontidz), 4 : c, Nanomys minu- ponding teeth of Ptilo- 
tus. After M ae All type ianei 
dus. The premolars of 
this genus are, of course, found in the species of Halodon. The 
premolar referred to H. serratus agrees best in size with the molars 
of C. gracilis. i 
The accompanying restoration of the upper and lower jaws of 
Cimolomys gracilis shows the various relationships of this animal 
as given in the above diagnoses by the author : 


~- Cimolomys gracilis 
ao XN 
N Cimolomys bellus 
E4 Epen. 
Halodon Nanomys minutus 
Plagiaulacidæ | ee Cimolodonuies: 
rratus -== # too Cimolodon nitidus 
} Cimolomidz. 
FIG. 4.—Upper and lower molars and premolars of ? Cimolomys, in position, 
These relationships will probably be increased, rather than 
diminished, by future discoveries.“ As it is, an upper and lower 
jaw referred to three families, five genera, and five species, is with- 
out precedent in paleontological literature. 
8. Dipriodon robustus (PL. 11., Figs. 13-15). The type is prob- 
ably correctly described as a last upper molar of the left side; it 
is referred to a new family, the Dipriodontide. 
13 See Allacodon lentus, which belongs either to this genus or to Meniscoéssus. 
mo 

