Samuel, et al:
The vertebra was 2.4 m tall (around 8 foot tall). It was called:
_Amphicoelias fragillimus_ :
My references say that the specimen (one bone) was badly damaged (but
nearly complete) when found, and it was the 9th or 10th dorsal vertebra, and that
it was lost during transference of Edward Drinker Cope's collection to the
Academy of Natural Sciences of Phila. (ANSP). Cope estimated that the length
of the femur could have been more than 3.5 meters (~12 feet). I believe
that the bone was crumbling back then, which is why Cope named it so.
I have suggested that parts of it may still be hidden in the ANSP
collections - much like a set of Cope's 1893 fossils were (rediscovered
around 1990). However, Ted Daeschler and Thom Holmes apparently searched
every area that could be searched at the Academy - and I know that they
would love to have found it (I was among a group of people who were there
when Ted found the 1893 fossils). Also, Jack Horner had
catalogued nearly everything else in the Vertebrate Paleo collection back in
Osborn and Mook referred the _A. fragillimus_ to _A. altus_, which
McIntosh accepted in his review in 1990. They (Osborn & Mook) suggested
that it should be merged into _Diplodocus_. (Jack McIntosh thought it was
possibly within a 'subfamily' of Diplodocinae).
Only a drawing remains, which claims that the vertebra was 2.4 m tall,
making the animal about 45 m long and possibly the biggest land animal ever,
at 100 to 150 metric tonnes. Greg Paul has estimated its length as 40-60
meters long, which is 130-200 feet long. (DinoFest International
Proceedings 1996 (Publ. 1998)). He also indicated that a 'world record'
individual of that species could have weighed as much as 200 metric tonnes.
Hope this helps with your question: