3. ELASMOGNATHTJS. 261 



3. ELASMOGNATHUS. 



The internasal cartilage ossified nearly the whole length, the 

 bony piirt produced beyond the end of the nasal. 



Elasmognathus, Gill; Gray, P. Z. S. 1867, p. 885, 



Elasmognathus Bairdii. B.M. 



Fur very short, close, dark black-brown ; lower part of the cheeks 

 and sides of the neck bay-brown ; chin, throat, chest, and front edge 

 of the shoulders greyish white. 



Young, bom with pale sti-ipes, VerriU, Silliman's Amer. Joiati. Sci. 



July 1867 ; Ann. ^- Ma;/. N. H. 1867, xx. p. 232. 

 Elasmognathus Eairdii, Gi'l(?), fide VerriU; Gray, P. Z. S. 1867, 



p. 885, t. 42. 



Hab. Panama : skull, Mus. CoU. Surgeons ; Brit. Mus., adult and 

 young skull. 



The internasal septum is continued between the elevated sharp 

 upper edges of the maxillaj, and even between the upper edges of the 

 intermaxilla. It remains cartilaginous until it reaches its adult size, 

 and then becomes ossified, forming a thick bony erect plate. 



In the younger skuU the cartilaginous septum is produced nearly 

 to the root of the cutting-teeth ; but in the older skuU, where the 

 septum has become ossified, the front parts of the iutennaxilla are 

 produced, and the septum ends over the root of the canines. The 

 shortness of the nasal cavity and the sharp-edged crest of the 

 maxilla) distinguishes the skull from those of the Tapirs in aU ages. 



The sides of the face of the skuU are flattened ; the zygomatic 

 arch and the front of the orbit over the prcorbital foramen is ex- 

 I^anded, flattened, and compressing the foramen into an oblong erect 

 shape ; the upper edge of the orbit is narrow and flat, not produced 

 into lobes as in the American Tapir ; the nasal bones are narrow, 

 longer than broad at the base, with an oblong deep concavity on 

 each side of their base, which is continued upwards behind it, so 

 as to be only separated by a small central ridge ; the hinder pala- 

 tine nasal opening varies in size in the two sexes, or it becomes much 

 wider and broader in front as the animal increases in age. In the 

 skull with the cartilaginous internasal septum, and only four grinders 

 in each side, the conca^ity containing the internal nostrils is narrow 

 and oblong. In the older skull with the septum entirely bony, and 

 with seven grinders in each side, the concavity containing the intenial 

 nostrils is much broader, being nearly as wide as long, and the vault 

 is more evenly rounded. 



The young animal, like the young of the Brazilian and other Tapirs, 

 is spotted and striped with white, ilr. Sclater kindly lent me a 

 photograph of a yoimg Panama Tapir ; and a copy of the photo- 

 graph was added to Mr. Wolft"s figui-e (P. Z. S. 1867, pi. 42) of 

 the half-grown animal, which Mr. Salvia obtained for the British 

 Museum. 



