THE STRUCTUEE AND RELATIONSHIPS OF ANCODUS. 
461 
THE STRUCTURE AND RELATIONSHIPS OF ANCODUS. 
By W. B. Scott. 
(Investigation aided by a grant from the Elizabeth Thompson Fund of the A. A. A. S.) 
It might well seem that after the extensive investigations of Kowalevsky (No. 
3) and Filhol (No. 1) any detailed description of the structure of this genus would 
be entirely supertluous. This, however, is far from being the case. The Kuropeiin 
specimens are made up from scattered bones of numerous individuals from widely 
separated localities (some of which bones would appear to be incorrectly referred to 
this genus), which by no means give a complete account, of the osteology ol the mmi- 
erous Old World species. In the second place, it is very desirable to establish the 
points of resemblance and difference between the approximately contemporaneous 
species of Ancodus in America and Europe. In both continents the genus is con- 
fined to the (upper) Oligocene and has, therefore, but a limited range m tune. 
Hitherto little has been known of the American species of Ancodus, because ol’ 
theB- rarity and the fragmentary condition of most of the specimens, since only in 
the recently identified Protoceras-beds are they at all common. Leidy was the brst 
to announce the presence of the genus in this country; he described part of the 
dentition of a White River species under the d Hyopotamus americamis No. 
5 p 202) Marsh has given an extremely brief account of another species winch 
hVna, J H. defiectus (No. 6, p. 024). Both of these ,pc<:i» are from the , tao 
therium-beds at the base of the White Eiver g.-o„p. In lOOo ' 
the manue of a epecies from the Protoceraa-bede at the sunmntot he ' ■ • 
Shotvina that it possessed a weii-developjed pollex (N... J, p. llw). t'sl,,.iii ,nii 
Wortmaa ha.e recently described .,ul figured a line 
eehieh eras coiieeted in t^ ^ t H ti::"!;* --- 
and have also added to the Araciic oiQ-^oi Ho- (LA and B). 
ture dealing tvith tine f ‘ Dakota by the Prineetoa 
In the e^pteattons of ti e h.tejwe, ^ 
Expeditions ol lSdo and U JT) , sandstones of the Prolo- 
:Lt-;:Zld IcMir subject of the following description. These speci- 
