Male UC (pl.III, figs.1-4) [p.199-200]
#The male UC is a large conical tooth elongated in antero-posterior (MD?) direction
#The ant border is convex vertically & is rounded; the post border forms an edge & is straight or slightly concave from the tip to the base
#At the lingual surface there is a vertical groove, close to the ant border & following [mengikuti] its curve. Usually it is distinct only in the middle of its curve & fades away [berangsur hilang] toward the tip & toward the base. It may [mungkin] have weakly developed (no.20, pl.III, fig.3)
#Behind it the lingual surface forms a ridge which may [mg], or may not, be defined [membatasi] posteriorly by a groove. If this post groove is as distinct as the ant groove, the lingual surface as a whole is trilobate (no.28, pl.III fig.4)
#There also may be a sharp vertical groove near the base about in the middle of the lingual surface & another one half way between ant groove & post border, which runs to the tip (no.2, pl.III, fig.2)
#Instead of some distinct groove the lingual surface behind the vertical ridge may show a number of minor grooves (no.1, pl.III, fig.1)
#The gingival line may be slightly concave toward the root along the labial surface; at the ant border it’s sometimes a little produced toward the crown.
#A cingulum is discernible [kelihatan] only at the lingual surface, it may forms a low cusp at the post border (no.28, pl.III fig.4)
Female UC (pl.III, figs.5-9) [p.201]
#The UC of female orang utan differs from that of male individuals in its smaller size, relatively lower crown & better developed lingual cingulum.
#In keeping w/ its smaller size, the labial surface of the female UC is more convex from before backward than that of the male UC.
#The ant border of the crown is more rounded than the post; it may also forms an edge (nos.2, 20-22)
#near the base of the crown it passes into a triangular prominence, the ant formation of the cingulum. At this point the gingival line often presents a concavity toward the root.
#The post edge of the crown is longer than the ant & forms a prominence at the base which is less developed than that at the ant side.
#Along the whole of the lingual surface the cingulum forms a band which more often is well-marked off [menandai, membedakan] from the surface itself & which may bear a central tubercle (no.3, pl.III fig.7)
#The ant groove on the lingual surface which occur in the male UC is not invariability [ketetapan] presents in the female UC; it may be weakly developed & even completely absent. There is always a more or less defined [mempertegas] vertical ridge anteriorly of the middle of the lingual surface, as in the male UC; behind it the surface is depressed & possesses a number of minor grooves & ridges. A sharp vertical furrow in the middle of the lingual surface is characteristic for some specimens (nos.23,25&34; pl.III figs.6,8&9). Occasionally the latter furrow even cuts through the cingulum & is continued for some distance on the root (no.34, pl.III fig.9)
#The root is preserved in 4 specimens only. It’s conical; its antero-posterior diameter exceeds the transverse diameter. The body is regularly curved backward, the labial surface is convex, the lingual possesses a longitudinal depression
#The height index=antero-posterior diameter x 100/vertical diameter
#Like the male UC, the UC of the females is larger in the subfossil race than in the recent. The difference in the height index has no statistical important, but that in the antero-posterior diameter is greater than three times its standard error, as can be seen from table 15.