LANCE FLORA OF EASTERN WYOMING 151 



Viburnum? probkmaticuin Knowlton, U. S. Geol. Surv. Bull. 163, 71, pl. 19, fig. 4, 1900; U. S. Geol. Surv. Prof. 



Paper 101, 276, pl. 49, fig. 9, 1917. 

 Vihumum whymperi Heer. Knowlton, Proc. Washington Acad. Sci., vol. 11, 207, 1909. 



There are 5 nearly complete specimens, from three localities, which I cannot distinguish 

 from the type and figured specimens of Viburnum montanum or F.? problematicum. As was 

 pointed out in my discussion of these species in the report on the Medicine Bow flora, there is a 

 likehhood that the collection of a larger suite of leaves of this f orm would show that several other 

 species, such as V. contortum Lesquereux and V. speciosum Knowlton, are actually synonymous. 



From an examination of the Lance Creek collections at the U. S. National Museum it is 

 clear that the specimens assigned by Knowlton to V. whymperi Heer are in reaUty referable to 

 V. montanum. 



OccMT-rence— LocaUties P3652, P3854, P3857. 



Collection~\]. C. Mus. Pal., Plesiotypes Nos. 2551, 2552; No. 2553. 



DICOTYLEDONES, Position Uncertain 



Anona? robusta Lesquereux 

 (Plate 15, Fig. 4) 



Anrnia robusta Lesquereux, Rept. U. S. Geol. Surv. Terr., vol. 8, 124, pl, 20, fig. 4, 1883. Knowlton, U. S. 



Geol. Surv. Prof. Paper 130, 143, pl. 17, fig. 7, 1922. Brown, U. S. Geol. Surv. Prof. Paper 189, 251, pl. 



54, fig. 2, 1939. 

 Ficus uncata Lesquereux. Knowlton, U. S. Geol. Surv. Prof. Paper 101, 301, pl. 76, fig. 2, 1917. Dorf, BuU. 



Geol. Soc. Amer., vol. 51, 218, 222, 225, 1940. 



The collections contain 5 weU-preserved though incomplete specimens, of which the best is 

 figured, which agree in essential characteristics with the specimens referred by Lesquereux and 

 Brown to Anona robusta. I had provisionally called the Lance Creek specimens Ficus uncata. 

 Both the description and the original type specimens of the latter species show, however, that the 

 secondary veins are prominently branched on their lower sides. This is not the case in the Lance 

 Creek specimens nor in the Raton specimen which Knowlton referred to F. uncata. 



As here conceived, this species is now known from the Laramie and Raton formations and 

 from the Lance of both Wyoming and Montana. I have not seen any species in the true "Fort 

 Union " or other beds of known Paleocene age with which this leaf form might be confused. 



The modern relationships of this species are doubtfully known. The original reference to 

 Anona is a reasonable one, though there are genera of both the Magnoliacese and the Moraceae 

 which seem equally comparable. 



Occurrence — Localities P3853, P3855. 



Collection—V. C. Mus. Pal., Plesiotype No. 2554. 



Apeibopsis? discolor (Lesquereux) Lesquereux 



Apeibopsisf discohr (Lesquereux) Lesquereux, Rept. U. S. Geol. Surv. Terr., vol. 7, 259, pl. 46, figs. 4-7, 1878. 



Dorf, BuU. Geol. Soc. Amer., vol. 51, 218, 222, 225, 1940. 

 Rhamnus discolor Lesquereux (in part), U. S. Geol. and Geog. Surv. Terr., Ann. Rept. (1872), 398, 1873. 

 Liriodendron sp., Brown, U. S. Geol. Surv. Prof. Paper 189, 251, pl. 52, fig. 7, 1939. 



There are 10 specimens, from three localities, which are sufficiently complete and well 

 preserved to be identified with this species. On consulting the type specimens at the U. S. Na- 

 tional Museum, it appeared evident that the incomplete Colgate leaves which Brown referred to 

 Liriodendron sp. cannot be distinguished from the original types of Apeibopsis? discolor from the 

 Black Buttes flora or from the Lance Creek specimens. 



I suspect that the single specimen from Black Buttes which Lesquereux named Ficus 

 haydenii ' is in reality conspecific with those from the same locality referred to Apeibopsisl discolor. 

 In view of the fact that the type specimen of Ficus haydenii is at present not to be found, how- 

 ever, it seems advisable to await its discovery before making a final allocation. 



' Lesquereux, L., Rept. U. S. Geol. Surv. Terr., vol. 7, 197, pl. 30, fig. 1, 1878. 



