TRICHECHUS. 37 
Skull arched, descending rapidly anteriorly from frontals to 
nasals; zygomata large and massive; jugal greatly developed. Orbit 
small, prominent, almost inclosed by bone; anterior nares lozenge- 
shaped, extending behind orbits. The mandible is massive, with a 
horny plate attached anteriorly, which supplies the place of teeth. 
Molar teeth in both jaws similar in character, square enameled 
crowns elevated into transverse tuberculate ridges; those in the 
upper rows having two ridges and three roots, those in the lower 
three ridges and two roots. 
25. manatus (77richechus), Linn., Syst. Nat., 1, 1758, p. 34. 
manatus (Manatus), Linn., Syst. Nat., 1, 1766, p. 49. 
latirostris (Manatus), Harl., Journ. Acad. Nat. Scien. Phil., 1824, 
p. iii. Elliot, Syn. N. Am. Mamm., 1901, p. 6. 
australis Tilesius, Jahrb. Naturg., 1, 1802, p. 23. 
americanus Desm., Dict. Hist. Nat., 1817, p. 262, pl. 96. (Part.) 
fluviatilis Schreb., Saugeth. Suppl., 1846, pl. 379. 
MANATEE. Vacca de Agua, in Guatemala. 
Type locality. East coast of Florida near the Cape. 
Geogr. Distr. Florida coast to Yucatan, Mexico. 
Genl. Char. Those of the genus. 
Color. Grayish black over all the body. 
Measurements. Total length, 2268. Skull: total length, 380; 
zygomatic width, 220; interorbital constriction, 70; palatal arch to 
end of palatal floor, 155; length of mandible, 215; height at coronoid 
process, 135. 
