PLAGIAULACODON——PLANOPS. 541 
Plagiaulacodon— Continued. 
which Falconer states that the latter name is **an abbreviation for ‘Plagiau- 
lacodon, from zA&y10c, oblique, and «vAa$&, groove, having reference to the 
diagonal grooving of the premolars.”’ 
ce 
Extinct. 
Plagiaulax Fatconrr, 1857. Allotheria, Plagiaulacid:e. 
Quart. Journ. Geol. Soc. London, XIII, pt. 3, No. 51, pp. 262-282, figs. 1-5, 7— 
15 in text, Aug. 1, 1857. 
Species: Plagiaulax becklesii Falconer (type), and P. minor Falconer, from the 
Upper Oolite (Purbeck), Dorsetshire, England. (Abbreviation for Plagiau- 
lacodon. ) 
Extinct. 
Plagiaulax: mA aytos, oblique; avAaé, groove—irom the obliquely grooved pre- 
molars. 
Plagiocoelus AMEGHINO, 1894. . Monotremata (Adiastaltide). 
Enum. Syn. Mamm. Foss. Form. Éocénes Patagonie, 186-187, Feb., 1894. 
Type: Plagiocoelus obliquus Ameghino, from the Eocene of Patagonia. 
Extinct. 
Plagiocoelus: zÀA&y10s, oblique, transverse; Koi os, hollow. 
Plagiodon Arsrow, 1876. Glires, Octodontidze. 
Proc. Zool. Soe. London, 1876, 93. 
Emendation of Plagiodontia Cuvier, 1836. 
This form is preoccupied by Plagiodon Duméril, 1853, a genus of Reptilia. 
Plagiodontia F. Cuvier, 1836. Glires, Octodontidz. 
Ann. Sci. Nat., Paris, 2° sér., VI, 347-353, pl. 17, Dec., 1836. 
Plagiodon Auston, Proc. Zool. Soc. London, 1876, 93 (preoccupied ). 
Type: Plagiodontia xdium F. Cuvier, from Haiti, West Indies. 
Plagiodontia: zA&yi0os, oblique; ddo0vs, óÓóvroc, tooth—from the diagonal 
grooves of the upper molars. 
Plagiolophus Pome, 1847. Ungulata, Perissodactyla, Paleeotheriide. 
** Bull. Soc. Géol. de France, 2° sér., IV, 586, Apr. 5, 1847;" Archiv. Sci. Phys. 
et Nat., Bibl. Univ. Genéve, V, 202, June, 1847; Cat. Méth. Vert. Foss. Bassin 
de la Loire, 82-83, 1854 (exact date of publication *); Bravarp & PowEr, Notice 
Ossem. Foss. de la Débruge, prés Apt, p. 6, 1850. 
Species: Palaotherium minus G. Cuvier, and P. minimum G. Cuvier, from France. 
Extinct. 
Plagiolophus: tA. ayios, oblique; Ad@os, crest. 
Planiceros (subgenus of Bubalus) Gray, 1872. Ungulata, Artiodactyla, Bovidee. 
Cat. Ruminant Mamm. Brit. Mus., 10-12, 1872. 
Species, 3: Bubalus brachyceros Gray, B. centralis Gray, and Bos reclinis Blyth, 
from Africa. 
Planiceros: Lat. planum, level, flat; «éeas, horn—from the depressed, flat horns. 
Planodus AMEGHINO, 1887. Ungulata, ? 
Enum. Sist. Especies Mamíft. Fós. Patagonia Austral, p. 20, Dec., 1887; Act. Acad. 
Nac. Cien., Córdoba, VI, 619, 1889. 
Type: Planodus ursinus Ameghino, from the lower Tertiary of southern Patagonia. 
Extinct. 
Planodus: zÀ&vos, deceiving; dd0vs , tooth. 
Planops AMEGHINO, 1887. Edentata, Megalonychid:e. 
Enum. Sist. Especies Mamíf. Fós. Patagonia Austral, p. 23, Dec., 1887. 
Type: Planops longirostratus Ameghino, from the lower Tertiary of southern 
Patagonia. 
Planops: zA&vos, deceiving; oy, aspect. 


* Paloplotherium Owen is quoted as a synonym dating from June 16, 1847; this, 
however, is probably the date of reading and not of publication. 
