In punctatus there are teeth on the vomer, in unimaculatus none, in norvegicus they are very small.
"Hormones and Heredity"
J. T. Cunningham
The first cranial peculiarity is that in Telemetacarpi, as a rule, the vertical plate developed from the lower surface of the vomer is prolonged sufficiently downwards and backwards to become anchylosed to the horizontal plate of the palatals, forming a septum completely dividing the nasal cavity into two chambers.
"Natural History of the Mammalia of India and Ceylon"
Robert A. Sterndale
The nasal fossae are situated on either side of the median partition formed by the vomer and cartilaginous nasal septum.
"Surgical Anatomy"
Joseph Maclise