FORT UNION OF CRAZY MOUNTAIN FIELD, MONT. 



61 



Table 4. — Composition {in percentages) of the principal No. 2 surface localities 

 and of each of the three quarries, Crazy Mountain Field, Mont. 



Order and family 



Scarritt 

 Quarry 



MULTITUBEECULATA : 



Ptilodontidae 



Insectivora: 



7Deltatheridiidae- - 



Leptictidae.. 



Nyctitheriidae 



Pantolestidae 



Mixodectidae 



Picrodontidae 



Incertae sedis 



Primates: 



Plesiadapidae 



Carpolestidae 



7Anaptomorphidae. 

 Inoertae sedis 



Taeniodonta: 



Stylinodontidae 



Oarnivora: 



Arctocyonidae 



Miacidae -. 



Mesonychidae 



Condylarthra: 



Hyopsodontidae. . . 

 Phenacodontidae.. . 

 Periptychidae 



Pantodonta: 



Pantolambdidae. - . 



' Represented by 1 specimen (less than 0.5 percent). 



The figures represent the composition of the identified collections. 

 They are somewhat biased in favor of the multituberciilates, since 

 practically all the specimens of these are identified, whereas there 

 are numerous isolated teeth of other orders that are not identified, 

 but in general they are representative of the faunas as they occur. 



The Gidley and Silberling Quarries agree well, within the probable 

 Hmits of chance, except for the much smaller proportion of primates 

 and greater of multituberculates in the Silberhng Quarry, a differ- 

 ence probably representing slight local facial distinction. 



The surface localities differ remarkably from the quarries and sug- 

 gest very different environmental conditions. This result is doubtless 

 somewhat biased by the fact that minute forms, like insectivores and 

 primates, are more likely to break up and are harder to find at sur- 

 face localities, but this does not explain the difference. Some of the 

 so-called surface material was, in fact, found in place. These locali- 



