_TAPIRUS. 97 
Regions ; but these have gradually disappeared, leaving their representatives at the two 
most distant extremities of their once extensive range. As far as the New World is 
concerned, the Tapirs are thus now an exclusively Neotropical type. 
Fam, I. TAPIRIDA. 
I. TAPIRUS. 
Tapirus, Brisson, Régne Anim. p. 118 (1756). 
Hydrocherus, Erxleben, Syst. Reg. An. p. 191 (1777). 
The few existing species of Tapirs present well-marked cranial features in addition to 
their external differences. Of late years it has been proposed to regard these characters 
as of generic value, the late Dr. Gray having separated the Malayan Tapir under 
Wagner's name of Rhinocherus*, and Dr. Theodore Gill the Central-American species as 
Llasmognathusy. The skulls of the latter certainly present very striking characters : 
in some respects they resemble that of Tapirus indicus rather than those of T. ameri- 
canus and 7. rowlint; but in others they differ from all the other known species. Of 
these the most remarkable is the complete ossification of the mesethmoid, which forms 
a bony nasal septum, extending in the adult skull far in front of the short nasal bones, 
and clasped below by ascending plates developed from the maxillaries. Dr. Gill no 
unnaturally anticipated that these cranial characters would be found to be correlated 
with external peculiarities in the head and proboscis, and with consequent modification 
of habits; but not only has this ‘proved not to be the case, but the two forms of 
Elasmognathus differ from each other in much more important cranial characters than 
they do from any of the other Tapirs. Under these circumstances it seems to me to 
be unwise to attempt to break up such a small and well-defined genus as Tapirus. 
Five years after his first description of Elasmognathus bairdi, Dr. Gill announced the 
discovery of a second species of the genus, based on the examination of a series of five 
skulls sent to the Smithsonian Institution from Guatemala by Captain J. M. Dow. 
He proposed to name the form L. dowi, and gave the following preliminary notice of 
its remarkable cranial peculiarities :— | 
“‘The most obvious differences are in the development of the nasal and frontal 
bones; but these are confirmed by the differences in the dentition, especially in. the 
form of the first premolar of each jaw. The nasal bones of the young, compared with 
those of the corresponding age of E. bairdii, are wider, especially in front of the * pits,’ 
and exhibit basilar processes recurrent forward.along the frontal [maxillary ?] bones, 
like those of Tapirus, but less developed, and .the grooves for the nasal cartilages are 
deeper. As the animal advances in age, however, the frontals would appear to grow 
forward and force apart the nasals, which apparently do not increase, or even diminish 
* P. Z.8. 1867, p. 884. f Proc. Acad, Philad. 1865, p. 183; Amer. Journ. Science, 1. p. 142, 
BIOL. CENT.-AMER., Mamm. Vol. 1, April 1880. O 
