Ankylosaurus/ankylosaur

[Amado Narvaez <anarvaez@umd5.umd.edu>]

I work in an elementary school where dinosaurs are, of course, very
popular. I'm not sure that the teachers and students understand that
there is a difference between an Ankylosaurus and an ankylosaur, or
a Tyrannosaurus and a tyrannosaur. While working on a hypermedia
program about popular dinosaurs, I realized that particularly with
Ankylosaurus, there seems to be considerable misconceptions about
its appearance.

A check of _The Dinosaur Encyclopedia_ by Lessem & Glut revealed
information on misconceptions regarding the "high arch" of the
skeleton (or the lack thereof). They explain that Ankylosaurus was
"built lower to the ground." Later in the same paragraph, they write:
"The armor pattern of Ankylosaurus was similar to that of its earlier
relative, Euoplocephalus." There is no picture of Ankylosaurus in the
book (pp 34-35). The Euoplocephalus entry (pp 188-189) shows both
a reconstruction and the skeleton of this ankylosaur.

David Lambert's _The Ultimate Dinosaur Book_ has entries on
Euoplocephalus, Sauropelta, and Edmontonia, but not Ankylosaurus.
If you were to put the four animals in a line up and asked five
lay dinosaur enthusiasts to pick out Ankylosaurus, would they
likely ignore Ankylosaurus completely in favor of any one of the
other three? (I include myself as a lay dinosaur enthusiast.)
Am I correct in my impression that the only sharply pointed features
on Ankylosaurus were on the head, and that there were no spikes at
all on the body?

Why do the better dinosaurs books, like Lambert's and David Norman's
_The Illustrated Encyclopedia of Dinosaurs_, prefer ti depict
Euoplocephalus  rather than the ankylosaur whose name the public
is most familiar with? (Speaking of Dr. Norman's book. On page 
164-165 there is a picture of Euoplocephalus and Pinacosaurus.
Would I be right in saying that Pinacosaurus looks much more like
Ankylosaurus than Euoplocephalus does, since it does not have the shoulder
and back spikes?)

----- Amado Narvaez
      anarvaez@umd5.umd.edu