All Aboard! 20th Century American Trains which contained four sets of the five paintings. All Aboard! 20th Century American Trains In August 1999, the United States Postal Service issued a set of 33¢ postage stamps entitled All Aboard! 20th Century American Trains to ""pay tribute to American industry and design, and specifically to the heritage of our railroads."" Artist Ted Rose created five watercolor images depicting the following celebrated American named passenger trains from the 1930s and 1940s: Descriptive text regarding each of the trains was listed on the gummed side of each stamp. At the same time, the USPS offered for sale a booklet of
20th century in ichnology excavation of fossil footprints in history. In the Lee Stokes reported unusual footprints he interpreted as the first known pterosaur tracks. This attribution would be controversial much of the rest of the century but has since been vindicated. The dinosaur footprints of Dinosaur Ridge in Colorado were also discovered and studied in the 20th century. The advent of the dinosaur renaissance and the publication by R. McNeil Alexander of a formula which could reconstruct their running speed based on data from fossil trackways brought renewed interest and prestige to ichnology during the late 20th century. This led to several symposia