INDEX. 



131 



Page. 



Mylagaulidse 77, 78, 80, 81, 114, 116, 119 



Mylagaulus 78,81,119 



laevis 114 



monodon 116 



paniensis 114,116 



pristinus 116 



proximus 116 



sesquipedalis 116 



Mylodon 82,83,85,87,89 



sp 120 



Mylohyus 87,90 



Myotis 90 



N. 



Nanohyus. See Ictops. 



Nanomeryx 103 



caudatus 98 



Nebraska, fauna of 103-109 



formations in, homotaxis of 65 



figure showing 65 



Oligocene and Miocene in, map showing. 60 



Neohipparion 79, 80, 83, 1 1 9 



affine 117 



calamarium : 117 



dolichops 117 



eurystylus 117 



gratum 117 



ingenuum 117 



lenticularis 117 



montezumae 117 



niobrarense 117 



occidentale 117 



peninsulatum 117 



plicatile 117 



princeps 117 



rectidens 117 



reUctum 117 



retrusum : 117 



sinclairii 117 



speciosum 117 



whitne^i 117 



sp * 120 



Neoplagiaulax 100 



americanus 91 



molestus 91 



Neotoma 90 



New Mexico^ fauna of 35, 91-95 



formation of, homotaxis of 22 



figure showing 23,65 



Nimravus 68,75,110 



confertus 107 



debilis 107 



gomphodus 107 



sectator 112 



North Boulder Creek, Mont., fauna of 114-115 



North Dakota, fauna of : 106-109 



Notharctidse 46,52,92,95,98,100 



Notharctus.... 46,47,100 



affinis = 95 



anceps 95 



cingulatus 92 



minutus 93 



nunienus 92 



pahneri 92 



rostratus 95 



tenebrosus 95 



Pago. 



Notharctus, tyrannus 95 



uintensis 98 



venticolus 92 



sp 95 



Nothocyon 68,73,74,75,110,118 



annectens 112 



geismari anus 1 06 



gregorii 112 



latidens 106 



lemur 106,112 



vulpinus 112 



Notostylops zone, mammals of 33 



Nototherium 88 



Nyctilestes '. loi 



Nyetitherimn loi 



priscus 96 



serotinus 95 



velox 96 



O. 



Odocoileus 86,87,88,89,90 



Ogalalla formation, fauna of 79-81,115-118 



homotaxis of 79-81 



Olbodotes loi 



Oligobunis 66,75,110,118 



crassivultus 107 



lepidus 112 



sp 105 



Oligocene, distribution of, plates showing 7,60 



fauna of 57-69,103-111 



range of 110-111 



homotaxis of 57-69 



figures showing 64,65 



Oligocene, lower, fauna of.... 60-61,103-104,110-111 



homotaxis of 60-61 



figure showing 65 



Oligocene, middle, fauna of.. 62-63,105-106,110-111 



homotaxis of 62-63 



figure showing 65 



Oligocene, upper, fauna of 63-69,106-111 



homotaxis of 63-69 



figure showing 65 



Oligocene-Eocene correlation, progress of 31 



Oligocene-Pleistocene correlation, progress of. 31-32 



Oligotomus 102 



Omomys 100 



ameghini 95 



carteri 95 



minutus 93 



pucillus 95 



Onychodectes 102 



rarus 92 



tisonensis 92 



Oodectes 46,52,100 



herpestoides 96 



pugnax 96 



sp ^. 96 



Opisthotomus. See Phenacodus. 



Oregon, fauna of 106-109 



formations of, homotaxis of 22, 64 



figure showing 23, 65, 67 



Oreodon 67 



affinis.... 104 



buUatus 104,106 



coloradensis 106 



culbertsoni 106 



