The official postcard (of the <a href="https://en.wikipedia.org/wiki/American_Museum_of_Natural_History" class="extiw" title="w:American Museum of Natural History">American Museum of Natural History</a>) says this is a <i><a href="https://en.wikipedia.org/wiki/Barosaurus" class="extiw" title="w:Barosaurus">Barosaurus</a></i>, and that "this unique freestanding mount is the only <i>Barosaurus</i> on view in the world". This was true until the installation of another <i>Barosaurus</i> specimen at the Royal Ontario Museum. The adult specimen pictured is AMNH 6341, classified as <i>Barosaurus lentus</i>. The juvenile specimen (AMNH 7530), originally classified as a juvenile <i>Barosaurus</i>, has since been reclassified as a specimen of <i>Kaatedocus siberi</i>.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/54046101@N00">Greg</a> from New York, NY, America
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/54046101@N00/2219749760/">Christina fights the dragon</a>