906 INDEX GENERUM MAMMALIUM. 
INCERTZE SEDIS. 
Chronozoon Dx Vis, 1883 ........... Chronozoon australe, Darling Downs, Queensland. 
Dystomus G. FiscHer, 1813......... Dystomus sp. 
Protosirena HAECKEL, 1895 -..------ Hypothetical ancestor of the Sirenia. 
TILLODONTIA.^ 
ANCHIPPODONTIDZE. 
FAMILIES AND SUBFAMILIES. 
Anchippodontidae Gru, 1872. Tillotheride M ^Rsu, 1875. 
GENERA AND SUBGENERA. 
Name, authority, and date. Type or included species, and localities. 
Anchippodus Lripy, 1868....-..---- Anchippodus riparius, Shark River, New Jersey. 
Tillotherium MARSH, 1873...---.---- Tillotherium hyracoides, Wyoming. 
Trogosis LEIDY lS (esos Love eec Trogosus castoridens, Fort Bridger, Wyoming. 
ESTHONYCHIDZE. 
FAMILIES AND SUBFAMILIES. 
Esthonychidx Corr, 1885. Platycheropide LYDEKKER, 1887. 
GENERA AND SUBGENERA. 
Name, authority, and date. Type or included species, and localities. 
Hsthonya OPE Weide. see cee Esthonyx bisulcatus, New Mexico. 
Miolophus OWEN, 18602-22222 22552c - Miolophus planiceps, Sheppey, England. 
Platychzrops CHARLESWORTH, 1855... Platycherops richardsonii, Herne Bay, England. 
NOTOSTYLOPIDZE. 
Notostylopide AMEGHINO, 1897. 
GENERA AND SUBGENERA. 
Name, authority, and date. Type or included species, and localities. 
Acrostylops AMEGHINO, 1901 ........ Acrostylops pungiunculus, Patagonia. 
Anastylops AMEGHINO, 1897.......-- Anastylops vallatus, Patagonia. 
Catastylops AMEGHINO, 1901 ........ Catastylops pendens, Patagonia. 
Coelostylops AMEGHINO, 1901........ Coelostylops crassus, Patagonia. 
Homalostylops AMEGHINO, 1901 
Tsostylops AMEGHINO, 1902 
Hec ee Homalostylops rigeo, H. interlissus, Patagonia. 
Ebor icc eue Isostylops fretus, Patagonia. 
Monolophodon Rorn, 1903 .......... Monolophodon minutus, Rio Chubut, Patagonia. 
Notostylops AMEGHINO, 1897 ........ Notostylops murinus, N. bicinctus, N. parvus, 
Patagonia. 
Orthogeniops AMEGHINO, 1902....... New name for Orthogenium Roth, 1901. 
t Orthogenium Rorn, 1901 ..-.....-. Orthogenium ameghinoi, Patagonia. 
Otronia ROH, l90l Se eae ae Otronia mühlbergi, Chubut, Patagonia. 
Parastylops AMEGHINO, 1897........ Parastylops celodus, Patagonia. 
Pliostylops AMEGHINO, 1901......... Pliostylops magnificus, Patagonia. 
Polumonphis ROTH, wSO9Re =e eee Polymorphis lechei, Chubut, Patagonia. 
Tonostylops AMEGHINO, 1902........ Tonostylops spissus, Patagonia. 

* MaRSH, Am. Journ. Sci., 3d ser., IX, p. 221, Mar. 1875; see also WonTMAN, Bull. 
Am. Mus. Nat. Hist., N: Y., TX, pp. 61-63, 1897. 
