HOLLAND AND PETERSON: OSTEOLOGY OF THE CHALICOTHEROIDEA. 205 
Type Specimens: Cranium, lower jaw, three cervicals, limb bones, carpus, and 
tarsus. 
Location of Types: Cope Collection, American Museum of Natural History. 
Geological Horizon: Washakie, Wyoming (Upper Middle Eocene). 
GENERIC CHARACTERS: ‘‘Premolar crowns simple, premolar conids without meta- 
stylids, large hypoconulid on M3, fibula greatly reduced”? (Osborn). 
Genus PHYLLOTILLON Pilgrim. 
Pilgrim, “Notices of New Mammalian Genera and Species from the Tertiaries of 
India.’”’ Rec. Geolog. Survey of India, Vol. XL, pp. 684-640 (1910). 
Type: Macrotherium naricum Pilgrim, Rec. Geolog. Survey of India, Vol. XX VII, 
p. 156 (1908). 
Geological Horizon: Nari Beds, Bugti Hills (Aquitanian fide Pilgrim, Oligocene 
(2). 
GENERIC CHaracters: ‘‘Phillotillon naricus n. gen. This name is to replace 
Macrotherium naricum, a Chalicotheroid from the Nari series of the Bugti 
Hills. The new genus differs from the other members of the family by the 
greater elongation of its molars, but chiefly by the fact that in the upper 
premolars the large inner cusp is united to the ectoloph by a double instead 
of a single crest.”’ Pilgrim, J. c. 
This very brief account of the genus leaves us in doubt as to the meaning of 
the author. “The large inner cusp of the premolars”’ is connected with the ectoloph 
by two crests in the case of many of the Chalicotheroids, the dentition of which is 
known, e. g. Schizotherium, Moropus, and Macrotherium. If the writer in the use 
of the word “‘double’”’ means to indicate that there are two such crests, the generic 
value of the distinction disappears altogether. If, however, he means to point 
out that these two crests are double, that is to say showing duplicated parallel 
ridges on their upper projecting summits, such a fact might well indicate a generic 
difference, as such a conformation of these teeth has never hitherto been pointed 
out by any one. Without more exact information on this subject the new genus 
is only accepted in a provisional manner. It is placed among the Schizothertine 
because it apparently comes from the Oligocene, and therefore may be associated 
with and related to the earlier forms. 
