LANCE FLORA OF EASTERN WYOMING 127 



Aside from its occurrence in the type Lance flora, this species is known onl.y from the upper 

 Mesaverde group and the Vermejo formation. 

 Occurrence — LocaUties P3854, P3858. 

 Collection—lS . C. Mus. Pal., Plesiotypes Nos. 2453, 2454. 



Family SALVINIACE^? 



Genus SALVINIA (Micheli) Schreber 7 



Salvinia? sp. 



(Plate 4, Fig. 4) 



Salvinia sp., Knowlton, Bull. Geol. Soc. Amer., vol. 8, 133, 1897; Proc. Washington Acad. Sci., vol. 1 1 , 207, 1909. 



In the collections at the U. S. National Museum there is a single specimen, here figured, 

 which Knowlton regarded as belonging to the genus Salvinia. Unfortunately the two incomplete 

 pinnules on the specimen are too poorly preserved to bring out the details of venation and of pitting 

 which are essential for description or identification. 



Occurrence — U. S. Geol. Survey Locality 1462. 



Collection — U. S. National Museum, No. 40249. 



FILICALES, PosiTioN Uncertain 



Genus FILICITES Brongniart 

 Filicites knowltoni Dorf, n. sp. 

 (PIate4, Figs. 7,8, 10, 11) 

 Fern (gen. et sp. nov.), Knowlton, Proc. Washington Acad. Sci., vol. 11, 207, 1909. 



There are 1 1 well-preserved specimens of this species, of which 9 are in the collections of the 

 U. S. National Museum. 



Description — Pinnules relatively small, averaging 6-9 mm. long and 3-5 mm. wide, oblong- 

 elliptic, entire-margined, and with fine, numerous, anastomosing veins obliquely diverging from 

 an indistinct midrib; pinnules closelj^ spaced on pinna in alternate arrangement, attached only by 

 central part of base; ultiraate disposition of pinnae unknown; fertile parts not preserved. 



I have been unable to find any living or fossil ferns with which these delicate specimens can 

 be adequately compared. 



Occwrrence— Localities P3856, P3858; U. S. Geol. Survey Locality 1462. 



Collection—V. S. National Museum, Cotype Nos. 40250, 40250a (counterpart) ; U. C. Mus. 

 Pal., Cotypes Nos. 2455, 2456. 



Family EQUISETACE^ 



Genus EQUISETUM Linne 

 Equisetum sp. 

 (Plate 6, Figs. 2, 3) 

 Equiselum sp.?, Knowlton, Proc. Washington Acad. Sci., vol. 11, 207, 1909. 



There are 3 well-preserved specimens and several fragments of ribbed, jointed stems clearly 

 referable to the genus Equisetum. There is also an excellent specimen of this form in the Lance 

 collections from this same area in the U. S. National Museum (specimen No. 1007 [1462]). As is 

 usually the case, none of these specimens shows features of diagnostic value for specific identifica- 

 tion. In addition to jointed stems, the Lance Creek collections also contain a specimen (fig. 3) 

 which I regard as a pair of typical equisetaceous tubers, and another specimen (fig. 2) which is 

 clearly an impression of a nodal diaphragra. 



