The black horns, which are ringed in their basal portion, are comparatively short and not unlike those of the Asiatic serows in general characters, being subcylindrical, and curving slightly backwards.
In nearly all the other Pleistocene forms these teeth were subcylindrical in shape, with the summit of the crown (except sometimes in the first pair) forming a cup-like depression; enamel being in all cases absent.
Those of Phyrganea consist of bits of twigs or leaves cut to a suitable length and laid side by side in a long spirally-coiled band, forming the wall of a subcylindrical cavity.
The hemispheres are rather elongated and subcylindrical, the olfactory lobes are large and project freely in front of the' hemispheres, and the greater part of the cerebellum is uncovered.
In these diminutive ground-sloths the crowns of the cheek-teeth approached the prismatic form characteristic of Mega[lo]therium, as distinct from the subcylindrical type occurring in Mylodon, Glossotherium, &c.