Pteranodon
While the first "Pteranodon" wing bones were collected by Marsh and Cope in the early 1870s, the first "Pteranodon" skull was found on May 2, 1876, along the Smoky Hill River in Wallace County (now Logan County), Kansas, USA, by Samuel Wendell Williston, a fossil collector working for Marsh. A second, smaller skull soon was discovered as well. These skulls showed that the North American pterosaurs were different from any European species, in that they lacked teeth and had bony crests on their skulls. Marsh recognized this major difference, describing the specimens as "distinguished from all previously known genera of the order Pterosauria by the entire absence of teeth." Marsh recognized that this characteristic warranted a new genus, and he coined the name "Pteranodon" ("wing without tooth") in 1876. Marsh reclassified all the previously named North American species from "Pterodactylus" to "Pteranodon". He considered the smaller skull to belong to "Pteranodon occidentalis", based on its size. Marsh classified the larger skull, YPM 1117, in the new species "Pteranodon longiceps", which he thought to be a medium-sized species in between the small "P. occidentalis" and the large "P. ingens". Marsh also named several additional species: Pteranodon comptus and "Pteranodon nanus" were named for fragmentary skeletons of small individuals, while "Pteranodon gracilis" was based on a wing bone that he mistook for a pelvic bone. He soon realized his mistake, and re-classified that specimen again into a separate genus, which he named "Nyctosaurus". "P, nanus" was also later recognized as a "Nyctosaurus" specimen.
Cetiosauriscus
The sauropod fossil today known as "Cetiosauriscus stewarti" was discovered in May 1898 by clay workers in the area around Fletton to the south of Peterborough and east of the Great Northern Railway. Pits in this region expose the fossil-rich sedimentary rocks of the marine Oxford Clay, which is of middle Callovian age and today regarded as one of the classic geological formations of British palaeontology. The sauropod fossil possibly stems from NPBCL pit No. 1, which was the northernmost pit operated by the New Peterborough Brick Company Limited, and which produced the most vertebrate fossils. The discovery was brought to the attention of Leeds, who, after excavation, took the sauropod specimen to Eyebury, the Leeds' family home. In mid-August, after some cleaning and repairing of the specimen, geologist Henry Woodward visited Eyebury and produced a life-sized drawing of the remains for presentation at the British Association for the Advancement of Science Meeting. Following this presentation, on 17 August 1898, Henry Woodward returned with American palaeontologist Othniel Charles Marsh, who considered the sauropod to be closely related to the North American taxon "Diplodocus". Alfred Leeds offered the sauropod to the British Museum of Natural History (BMNH, now abbreviated as NHMUK) for £250, which would equate to about £30,529 in 2017. The NHMUK had earlier in 1890 and 1892 bought the First and Second Collections of Alfred Leeds, respectively. Woodward, Keeper of Geology at the NHMUK, had "great pleasure" to recommend to the Trustees of the NHMUK the fossil be purchased. The purchase was sanctioned on 25 February 1899, along with the purchase of assorted other remains for just over £357 (~£43,596 now), where the Leeds sauropod gained the accession number BMNH R3078 (now NHMUK R3078).