70 CONTRIBUTIONS TO PAL^ONTOLOGY 



the Judith River (?), Fox Hills, Colgate, Lance, and Medicine Bow floras. It is apparently most 

 abimdant in the lower Lance formation, from which I have collected a considerable number of 

 perfect specimens near Lance Creek, Wyoming, and near Buffalo, South Dakota. 



The reference to the genus Vitis seems reasonable though as yet not corroborated by asso- 

 ciated seeds, flowers, or wood. 



Occurrence — Elk Mountain road, Wyoming, Loc. P. 374. 



Collection—lJ. C. Mus. Pal., Plesiotype No. 1361. 



Family TILIACEiE 



Genus APEIBOPSIS Heer 

 Apeibopsis? laramiensis Knowlton 

 (Plate 14, Fig. 1) 

 Apeibopsis? laramiensis Knowlton, U. S. Geol. Surv. Prof. Paper 130, 159, pl. 7, fig. 4, 1922. 



There are 2 well-preserved, incomplete specimens from Locality P. 374 which are similar 

 except for their somewhat smaller size to the type and figured specimens of this species from the 

 Laramie formation. Its very truncate base, thick midrib, and thin, closely spaced, widely diver- 

 gent secondaries are easily recognizable and diagnostic. 



The generic reference has been justifiably questioned by ICnowIton. Until more complete 

 specimens are found, however, it is difficult to attempt a taxonomic revision. 



Occurrence — Elk Mountain road, Wyoming, Loc. P. 374. 



Collection—\J. C. Mus. Pal., Plesiotype No. 1362. 



Genus GREWIOPSIS Saporta 



Grewiopsis saportana Lesquereux 



(Plate 13, Figs. 1, 5, 6) 



Grentiopsis saporlana Lesquereux, Rept. U. S. Geol. Surv. Terr., vol. 7, 257, pl. 50, figs. 10-12, 1878; Brown, 



U. S. Geol. Surv. Prof. Paper, manuscript, 1937. 

 Aleurites eocenica Lesquereux, U. S. Geol. Surv. Terr., 6th Ann. Rept. (1872), 397, 1873. 

 Greu-iopsis ficifolia Ward, U. S. Geol. Surv., 6th Ann. Rept., 556, pl. 46, figs. 1, 2, 1886; idem, Bull. 37, 92, 



pl. 41, figs. 1, 2, 1887. 

 Grewiopsis eocenica (Lesquereux) Ivnowlton, U. S. Geol. Surv. Bull. 152, 114, 1898; Wasliington Aead. Sci. 



Proc, vol. 11, 207, 1909. 



This type of leaf is by far the most abundant at Locahty P. 374. Over 25 well-preserved 

 specimens were collected for study. The majority of these cannot be distinguished in any 

 essential detail from the type specimens from Black Buttes, Wyoming. These were originally 

 described as Aleurites eocenica by Lesquereux, who subsequently changed the name to Greiviopsis 

 saportana. In a later report Knowlton changed the name again to Grewiopsis eocenica, a procedure 

 which hardly seems justified, as has been pointed out by Brown. Knowlton also included Ward's 

 specimens of Grewiopsis ficifolia in this species, a reference clearly substantiated by the numerous 

 Medicine Bow specimens. In view of the large number of variants now available it seems appro- 

 priate to re-describe the species. 



Description {Supplementary) — Leaves elliptic-lanceolate to ovate, narrowing gradually to a 

 blunt, obtuse point and more abruptly to a symmetrical, cuneate base; length 4.5 to 9.5 cm. ; width 

 2.2 to 6.5 cm., widest below the middle; average dimensions apparently about 7.5 by 4.5 cm.; 

 petiole relatively thin, very long, up to 5 cm.; midrib heavy except near apex, fairly straight; 

 6 to 9 pairs of secondaries, mainly alternate, pinnate, approaching palmateness in basal pair, 

 leaving midrib at angles of about 30° near apex to as high as 60° ncar base ; venation craspedodrome, 

 the secondaries irregularly curved toward the margins where they usually branch into the mar- 

 ginal teeth, these branches being more numerous in lower secondaries; tertiary venation distinct, 

 uniform, the veins continuous or branched at angles approaching 90° to the secondaries; margin 

 finely serrate or denticulate, often inconspicuously; the teeth short, irrogular in size, and usually 

 closely spaced; texture subcoriaceous. 



