Answer: Taenia saginata: intact long segment of attached proglottids wrapped around a glass rod and carefully preserved inside of a cylindrical tube at Tulane University.
Given that the proglottids are longer than wide and quite large, it is easy place this into the Taenia genus. However, if you look carefully, you can also tell that the proglottids have been cleared so that the uterine branching pattern is visible; there are 15 or more primary uterine branches along one side of each proglottid consistent with T. saginata. What a beautiful display!
If you haven't already, please read the very poignant story that Florida Fan tells about his own experience with tapeworm infection. It is in the comments from this case (question section).