LANCE FLORA OF EASTERN WYOMING 137 



Exanaination of Brown's type specimens at the U. S. National Museum has shown that the 

 leaves are actually remotely dentate, though the coarse sandy matrix makes this feature incon- 

 spicuous. There is no doubt in my mind, therefore, that the Lance Creek forms are referable 

 to the species described by Brown. 



Knowlton had already encountered this type of leaf in his collections from the Lance Creek 

 area, which I have consulted at the U. S. National Museum. These were tentatively referred 

 by him to Sassafras sp. and Aralia sp. in his published lists, and to Aralia n. sp. (specimen No. 

 1017) in the collections. AII these specimens are essentially similar to those from my collection 

 and from Montana. 



As was pointed out by Brown, there is a general resemblance between this species and 

 Araliopsoides cretacea (Newberry) Berry (= Sassafras cretaceum Newberry) from the Dakota, 

 Raritan, and Magothy floras.' There is also a resemblance to Aralia veatchii Knowlton from the 

 Frontier formation.^ In both these species, however, there are differences from Platanophylliim 

 montanum in shape, venation, and marginal characters. 



After consulting all available herbarium specimens of the living species of Sassafras at the 

 New York Botanical Garden, I am convinced that the Lance specimens of this species are not 

 referable to the genus Sassafras. In Sassafras leaves the 3 basal primaries are always suprabasilar, 

 the lobes are entire and rounded, and the venation is lauraceous in character. In the modern 

 Platanaceae, on the other hand, the leaves are more like the fossils here concerned in shape, vena- 

 tion, and marginal characters. 



OccM/Tence— Localities P3854, P3855, P3857, P3859. 



Collection—lJ. C. Mus. Pal., Plesiotypes Nos. 2503, 2504, 2505. 



Platanophyllum platanoides (Lesquereux) Dorf, n. comb. 



Viburnum platanoides Lesquereux, U. S. Geol. and Geog. Surv. Terr., Ann. Rept. (1874), 314, 1876; Rept. 



U. S. Geol. Surv. Terr., vol. 7, 224, pl. 38, figs. 8, 9, 1878. Dorf, BuU. Geol. Soc. Amer., vol. 51, 218, 222, 



225, 1940. 

 Platanus platanoides (Lesquereux) Knowlton (in part), U. S. Geol. Surv. Buli. 152, 171, 1898. 

 Platanus sp., Brown, U. S. Geol. Surv. Prof. Paper 189, 249, pl. 59, fig. 4 oniy, 1939. 



There are 4 well-preserved, though not complete, specimens from Locality P3652 which are 

 referable to this species. Unfortunately the specimens are so curled in the matrix that they 

 cannot be adequately photographed and figured. 



Lesquereux distinguished this species from Viburnum marginatum Lesquereux by "the less 

 numerous, more open, lateral veins, whose branches are more curved in passing up to the borders, 

 and especially by the enlarged truncate or subtruncate base of the leaves." It may be added that 

 the coarse tertiaries, the large, obtuse teeth, and the presence of teeth along the basal edge of the 

 leaves are also diagnostic characters. 



Outside of its type locality at Black Buttes, Wyoming, this species has been described and 

 figured from the Raton,' the Denver," and the Laramie floras.'' The Raton and Laramie speci- 

 mens do not have the diagnostic characters of the species and have been referred to Viburnum 

 marginatum Lesquereux.^ The Denver specimen is a very inadequate one which does not, more- 

 over, have the truncate, enlarged basal characters of Platanophyllum platanoides. 



One of the Fox Hills specimens which Brown referred to Platanus sp., which I have seen, is 

 believed to belong to this same species. 



The platanoid character of these leaves is apparent. Following the trend of modern no- 

 menclators, it seems advisable, in the absence of definite proof, to refer the species to the less 

 positive genus Platanophyllum. 



Occurrence — Locality P3G52. 



Collection—V . C. Mus. Pal., No. 2506. 



' Berry, E. W., Maryland Geoi. Surv., Upper Cretaeeous, 879, pl. 74, fig. 3, pi. 84, figs. 1, 2, pi. 85, figs. 1-5, pi. 88, figs. 

 1-3, 1916. Lesquereux, Rept. U. S. Geoi. Surv. Terr., voi. 6, 80, pl. 11, figs. 1, 2, pi. 12, fig. 2, 1874. 



' Knowlton, F. H., U. S. Geol. Surv. Prof. Paper 108, 92, pl. 30. fig. 4, pi. 37, fig. 4, pl. 38, fig. 1, pl. 39, 1917. 

 s Knowlton, F. H., U. S. Geol. Surv. Prof. Paper 101, 323, pl. 95, fig. 4, 1917. 

 • Knowlton, F. H., U. S. Geoi. Surv. Prof. Paper 155, 82, pi. 36, fig. 5, 1930. 

 ' Knowiton, F. H., U. S. Geol. Surv. Prof. Paper 130, 146, pi. 13, fig. 1, 1922. 

 ' Dorf, E., Carnegie Inst. Wasli. Pub. No. 508, pt. I, 73, 1938. 



