The "E G Curtis" who owned two of these membership cards (and presumably also the third) must be Edward Gansevoort Curtis, who was a member of the Victory Base Ball Club of Troy when it was organized in 1859. He was the team's pitcher in 1859 and the early part of the 1860 season. See pages 50 and 52 below, from Peter Morris's article on the Victory Club in "Base Ball Pioneers, 1850-1870", including an enlargement of Morris's capsule biography of Curtis. Despite Morris's statement that Curtis moved to Washington after graduating from Rensselaer Polytechnic, he must have still been living in Troy in 1869-71, when the membership cards date from. However, the 1900 U.S. Census shows him living in Washington DC as Edward G. Curtis, born October 1837 in New York, listed as a civil engineer living in a boarding house, and single. Despite Morris's statement that he died in Washington, Curtis is buried in Green-Wood cemetery in Brooklyn. (See
https://www.findagrave.com/memorial/...sevoort-curtis)
As for the membership cards, the Unions of Lansingburgh, aka the Troy Haymakers, succeeded the Victory Club as Troy's premier team after the Civil War, and soon went professional. In 1868 they joined the National Association of Base Ball Players, and in 1869 (the year of the membership card) they had a record of 24-9-1, including a record of 12-8-1 against professional clubs. See the first page below, from Marshall D. Wright's "The National Association of Base Ball Players, 1857-1870". As noted by the OP, in 1871 the Unions were one of the charter members of the National Association of *Professional* Base Ball Players, considered the first professional sports league in the United States.
The Putnam Base Ball Club was also from Troy, New York, but it was an amateur club, and not a member of the National Association of Base Ball Players, as the Unions of Lansingburgh were. The Unions played the Putnams three times in 1870, beating them 59-17 on June 4, 13-5 on September 28, and 45-9 on October 17. See the second page below, also from the Wright book. These are the only records I can find of the Putnams playing any National Association teams, but they obviously must have been around in 1869 and 1871, presumably playing other local amateur teams. (Note: There was another Putnam Base Ball Club that was from Brooklyn, active from 1855 to 1860, but which is not heard of after 1862. William Ryczek has a detailed article on them in the book "Base Ball Founders", pp. 111-117.)
