John Cassin (1813-1869) was America's first serious bird taxonomist.  A Pennsylvania Quaker and businessman, Cassin become curator of the Philadelphia Academy of Natural Sciences in 1842, which housed the largest collection of bird skins then in existence.  With the support of Dr. Thomas Wilson and Spencer Baird , Cassin became familiar with birds from all over the world and described some 200 new species.  He wrote the text of several government scientific reports based on explorations of the American West and military records from the Mexican War.   In addition, Cassin, was paid $5,320 to draw, print and hand color 2,000 copies each of 38 plates of birds brought back from the Railroad Surveys (a total of 76,000 plates at a cost of 7 cents apiece).  When John T. Bowen, the famous lithographer, died during the production of the Railroad Surveys, Cassin married his widow and assumed control of the Bowen firm.  The bird prints from the Railroad Surveys were re-published by the Smithsonian Institute in 1860 and with text by Spencer Baird entitled the Birds of North America.  Ron Tyler observes that while bird illustrations under Cassin's oversight  "might not be as aesthetically pleasing as John James Audubon's  . . . neither are they are anthropomorphic or romantic" (Prints of the West).