150 CONTRIBUTIONS TO PAL^ONTOLOGY 



There are 2 nearly complete specimens and several incomplete impressions which are essen- 

 tially sirailar to the type and figured specimens referred to this species. The specimen here 

 figured, though somewhat broken and wrinkled, shows the characteristic features of shape, size, 

 and venation. In a second specimen, frora Locahty P3857, the lobing is soraewhat more pro- 

 nounced. A third specimen, from Locahtj' P3859, previously identified as Cissites lobatus Dorf,' 

 is now regarded as an incomplete specimen of Dojnbeyopsis trivialis. 



At the present time this species is described or reported from only the Laramie, the Medicine 

 Bow, and the type Lance formations. It is not known to occur, or to be confused with any com- 

 parable leaves, in beds of indisputable Paleocene age. 



I ara as yet uncertain of the relationship of this species to raodern forras; as previou.sly pointed 

 out, the resemblance to the leaves of the modern Dombeya is reraote. 



Occwrrence— Locahties P3652, P3853, P3857, P3859. 



CoUection—V. C. Mus. Pal., Plesiotypes Nos. 2545, 2546, 2547. 



Family CAPRIFOLIACE.E 



Genus VIBURNUM (Tournefort) Linn6 

 Viburnum marginatum Lesquereux 

 (Plate 14, Fig. 3; Plate 15, Figs. 1, 5) 



Vibumum tnarginatum Lesquereux, U. S. Geol. and Geog. Surv. Terr., Ann. Rept. (1872), 395, 1873; U. S. 



Geol. and Geog. Surv. Terr., Ann. Rept. (1873), 382, 410, 1874; U. S. Geol. and Geog. Surv. Terr., Bull., 



vol. 1, 380, 1875; U. S. Geol. and Geog. Surv. Terr., Ann. Rept. (1874), 306, 1876; U. S. Geol. and Geog. 



Surv. Terr., Ann. Rept. (1876), 510, 1878; Rept. U. S. Geol. Surv. Terr., vol. 7, 223, pl. 38, figs. 1, 4 only, 



1878; BuJl. Harvard CoU. Mus. Comp. Zool., vol. 16, 51, 188S. Knowlton, BuII. Geol. Soc. Amer., vol. 



8,145,1897; Jour. Geol.,vol. 19,361,370,371,1911. Berry, CanadaGeol.Surv. Mem. 182, 57, 1935. Dorf, 



Carnegie Inst. Wash. Pub. No. 508, pt. I, 73, pl. 15, figs. 3, 5, pl. 17, figs. 4, 5, 1938. Brown, U. S. Geol. 



Surv. Prof. Paper 189, 252, pl. 59, fig. 7, 1939. Dorf, BuU. Geol. Soc. Amer., vol. 51, 218, 222, 225, 1940. 

 Platanus heerii Lesquereux. Ward, U. S. Geol. Surv. 6th Ann. Rept., 552, pl. 40, figs. 8, 9, 1885; U. S. Geol. 



Surv. BuII. 37, 34, pl. 15, figs. 3, 4, 1887. 

 Platanus platanoides (Lesquereux) Knowlton (in part), U. S. Geol. Surv. Prof. Paper 101, 323, pl. 95, fig. 4, 



1917; U. S. Geol. Surv. Prof. Paper 130, 146, pl. 13, fig. 1, 1922. 

 Platanus guilUhnx heerii Knowlton, U. S. Geol. Surv. Prof. Paper 101, 323, pl. 96, fig. 5, pl. 97, fig. 1, pl. 98, 



fig. 2, 1917. 

 Platanus marginala (Ijcsquereux) Heer. Knowlton, U. S. Geol. Surv. Prof . Paper 155, 81 , pl. 36, figs. 2, 3, 1930. 

 Platanus aceroides latifolia Knowlton (in part), U. S. Geol. Surv. Prof. Paper 155, 76, pl. 33, fig. 1, 1930. 



About 30 well-preserved impressions of clearly defined leaves of this species were collected 

 from five of the Lance Creek locaUties. They differ in no essential details frora the original types 

 and nuraerous figured specimens previously reported. A fuU description and discussion of this 

 species was given in my paper on the Medicine Bow flora, cited above. I have subsequently 

 encountered 5 excellent unlabeled specimens of this species in the Vermejo collection at the U. S. 

 National Museum (specimcns Nos. 51287, 51288, 51289, 51290, 51293). 



It is becoming increasingly more apparent that Viburnum marginatum is an ideal index 

 species for Lancian age in the Rocky Mountain region. The widespread occurrences of this 

 species are confined to the sediraents lying conformably above the beds of the Fox Hills or late 

 Pierre age and below the non-dino.saur-bearing "Fort Union." In terms of dinosaurian zones, 

 V. marginatum is restricted to the Triceratops zone. Geographically the species is distributed 

 from southern Colorado to as far north as southern Saskatchewan. Its reraains, moreover, are 

 usually abundant and its characters are well defined and easily recognized. 



Occurrence— Localities P3652, P3853, P3855, P3857, P3859. 



CoUeclion—\J. C. Mus. Pal., Plesiotypes Nos. 2548, 2549, 2550, 2550a (counterpart). 



Viburnum montanum Knowlton 



(Plate 15, Figs. 2, 3) 



Vibumutn montanum Knowlton, U. S. Geol. Surv. Bull. 163, 73, pl. 19, figs. 1, 2, 1900; U. S. Geol. Surv. Prof. 

 Paper 101, 276, pl. 52, fig. 2, 1917. Dorf, Carnegie In.st. Wash. Pub. No. 508, pt. I, 75, pl. 17, fig. 2, 

 1938; Bull. Geol. Soc, Araer., vol. 51, 218, 222, 225, 1940. 



> Dorf, E.. BuU. Geol. Soc. Amer., vol. 61. 218, 222, 225, 1940. 



