We boarded again, and eventually got to p4, one stop away from the station.
The enamel pattern of p4 is like that in other members of the tribe (excepting the genus Pliogeomys).
p4 has an anterior cusp and three posterior cusps as in other members of the genus.
Of these parts, right m2, left coronoid process, right p4 and M1 and adjacent part of maxilla are lost.
In p4 a complete enamel plate covers the posterior surface of the posterior loph.
P3 and p4 are the teeth of the permanent dentition which ultimately push out the last milk teeth to be lost.
The posterior enamel plate of p4 disappears in the final stages of wear as the interrupted enamel pattern is formed.
The p4 is provided with four fully developed enamel plates, in the pattern characteristic of the tribe Geomyini.
In evolutionary sequence loss of enamel from M1 and M2 usually occurs after, but never preceding, the reduction of enamel on p4.
Accordingly, in the permanent dentition, p4 and M1 appear before P3 does, and m1 and m2 make their appearance before p4.