The ruminants are peculiar also in their dentition; in the so-called true ruminants there are no incisors or cutting teeth in the upper jaw, but the teeth of the lower jaw are opposed to a hard callous pad; the herbage is cropped by being nipped between these teeth and the pad, and detached by an upward motion; in some few, such as the musk deer, Chinese water deer and the rib-faced deer or muntjac the upper canines exist, and are largely developed.
"Natural History of the Mammalia of India and Ceylon"
Robert A. Sterndale
He says: In a large collection of the skins, skulls, and horns of this species, which I have received from all parts of India and Burmah, and in a considerable number of living specimens which I have examined, I have observed amongst adult animals so much difference in size and intensity of coloration that I have found it impossible to retain the muntjac of Java and Sumatra as a distinct species.
"Natural History of the Mammalia of India and Ceylon"
Robert A. Sterndale
I have received from Northern India perfectly adult, and even slightly aged, specimens of both muntjac and axis inferior in size to the average as presented by these species in Southern India.
"Natural History of the Mammalia of India and Ceylon"
Robert A. Sterndale