98 Cretaceous. 



Prof. O. C. Marsh* described, from Smoky Hill river, in Western 

 Kansas, Pterodactylus occidentalism P. velox, P. ingens, Grapulavus 

 (cnceps, Hesperornis regalis, Lestosaurus siinus, now Platecarpus simtcs, 

 L. fellx, now P. felix, L. latifrons, now P. latifrons, L. gracilis, 

 now P. gracilis, Rhinosaurus inicromus, now Liodon micromus, 

 JSdestosaxirus rex, now Clidastes rex, Ichthyornis dispar, Colono- 

 saurus mudgel, now Ichthyornis dispar; and from the greeiisand at 

 Hoi'nerstown, New Jersey, Graculavus velox, Graculavxs pumilus, and 

 PalcBotringa vagans. 



Dr. Joseph Leidyf described, from Texas, Otodus divaricatus; from 

 Kansas, Oxyrhina extenta; from New Jersey, Acrodus humilis; and 

 from Mississippi, Pycnodusfaba. 



F. B. Meek and J. H. KloosJ found the Benton Group underlying 

 the drift gravel and clay in the Sauk valley, in Minnesota. 



T. A Conrad§ described, from the Yellow Chalk, near the Saline 

 river, Kansas, Haploscapha grandis, and H. excentrica. 



And Prof. Leo. Lesquereux described, from the hard ferruginous 

 sandstone of the Dakota Group, in Kansas, Pterospermites quadratus, 

 now Pterophyllum quadratum, Pterospermites multiiiervis, now Ptero- 

 phyllum multinerve, Pterospermites haydeni, now Pterophyllum hay- 

 deni. Magnolia ensifolia, now Celastrophyllum ensifolium, Quercus 

 mudgei, now Protophyllum mudgei^ Aralia quinquepartita, Platanus 

 heeri, and Sassafras obtusits^ now Cissites ohtusus. From the reddish, 

 ferruginous, hard shale of the Laramie Group, below the Coal at 

 Evanston, Utah, Quercus negundoides, Betula stevensoni, Rhus evansi, 

 Jtiglans rhamnoides; from a grayish, fine-grained, hard shale on the 

 divide between the source of Snake river and the southern shore of 

 Yellowstone lake, Gymnogramma haydeni; and from six miles above 

 Spring canon, and top of hills between Fort Ellis and Botteler's ranch, 

 Colorado, Myrica amh^igua, Quercus ellisana, and Q. pealei. 



In 1873, Prof. Leo Lesquereux|| described the Lignitic Group, from 

 the Raton mountains, northward to Denver and Cheyenne, and then 

 along the LTnion Pacific railroad to Evanston. In passing obliquely 

 from the town of Trinidad to the Raton valley, in a northwest direction, 

 the stage-road gently ascends about 150 feet to a plateau which, at the 

 surface, consists of the black shale of the Fort Pierre Group, and 



* Am. Jour. Sci. and Arts, 3d ser., vol. 3 and 4. 

 t Proc Acad. Nat. Sci. 

 \ Am. Jour Sci. and Arts, 3d ser., vol. 3. 

 § 5th Rep. Hayden's U. S. Geo Sur. Terr. 

 II Hayden's 6th Rep. U. S. Geo. Sur. Terr 



