LANCE FLORA OF EASTERN WYOMING 107 



clear, are known only from deposits ranging from the top of the Colorado group be- 

 low to the top of the true Sphenodiscus-hea.Tmg Fox Hills above — i.e., Judith River, 

 Belly River, Ericson-Almond (Mesaverde), and Fox Hills; species restricted to 

 Lancian age are those known only from bedslyingbetween the top of the true Spheno- 

 discus-bearing Fox Hills and the top of the Tncemtops-bearing beds — i.e., Colgate, 

 Hell Creek, Medicine Bow, Laramie, Whitemud-lower Ravenscrag, Arapahoe-lower 

 Denver, and lower Dawson; those restricted to Paleocene age are those known only 

 from beds lying between the Tncemtops-bearing beds below and the true Lower 

 Eocene Wasatchian above — i.e., TuUock, Ludlow, Fort Union and equivalents, 

 middle and upper Ravenscrag, and Paskapoo. 



Formations whose position in Montanan, Lancian, or Paleocene time is uncer- 

 tain because of lack of convincing stratigraphic or palseontologic data are disre- 

 garded for the present. The correlation of most of these formations, including 

 the Fruitland, Kirtland, Vermejo, Whitemud, and "Laramie" (Black Buttes) of 

 southwestern W}'oming, is made below on the basis of their floral assemblages. 



An analysis of table 3 gives the foUowing summary of data regarding the outside 

 distribution of the type Lance species of plants: 



No outside distribution 13 



Outside distribution 57 



Total number of species 70 



Short-ranging species: Long-ranging species: Species of uncertain range . . 2 



Montanan 3 Montanan-Lancian-Paleocene . 3 



Lancian 28 Montanan-Lancian 17 



Paleocene 1 Lancian-Paleocene 3 



32 23 



The short-ranging species, which are considered most rehable for correlation 

 purposes, are as fohows: 



Sliort-ranging species restricted elsewhere to Paleocene age: 



Cercidiphyllum arcticum 



Short-ranging species restricted elsewhere to Lancian age: 



Anona? robusta Laurophyllum meeki 



Apeibopsis? discolor Laurophyllum wardiana 



Aristolochites brittoni Magnoliophylium cordatum 



Carpites lancensis Menispermites cockerelli 



Carpites verrucosus Nelumbo tenuifolia 



Carpites walcotti Palaeoaster inquirenda 



Cinnamomum? affine Pistacia eriensis 



Cissus? lobato-crenata Platanophyllum montanum 



Dombeyopsis colgatensis Rhamnus? minutus 



Dombeyopsis trivialis Sabalites eocenica 



Ficus? ceratops Saliciphyllum wyomingensis 



Fraxinus leii Salix lancensis 



Grewiopsis saportana Sequoia dakotensis 



Laurophyllum coloradensis Viburnum marginatum 



Short-ranging species restricted elsewhere to Montanan age: 



Menispermites knightii Selaginella? falcata 



Woodwardia? crenata 



