Temp. in Cretaceous "Montana"?

[sean.kerns@sdrc.com (Mr. Snakey)]

I put that in quotes, since I know that it wasn't called
Montana then, but you know what I mean.

In reading Horner's T. Rex book, I have come across temperature guesses
for the Cretaceous in the Montana area of an average temp.
or ~50-60 degrees F.

Now, I'm sure most of you already knew that, but I'm late to 
this game, and really, that temperature range surprised me.
For some reason, I had always pictured temps in the 80's, or
so (influence of bad movies, maybe?).
I had never thought of, T. Rex, for example, as a cold-weather
animal.

What are your feelings on the validity/lack thereof of this
general temperature range?

Were things really that cool? Horner also says it would have
been quite wet.... So now, instead of seeing dinosaurs in a
hot, steamy jungle, I'm picturing a rainy fall day. 

If this is true, doesn't that pretty much end once and for all
the idea of truly cold-blooded dinosaurs?
I know my snakes have a tough time any time the temp gets, and
stays, below ~65 F. In 50 degree weatehr, they'd be popsicles.

Ideas?

P.S. Stupid beginner question: I'd had the notion in my brain that
birds evolved from the theropod dinosaurs, but I read recently that
they eveolved from ornithiscians? Is that right? 
I don't knwo how I get confused like that.
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*  Snake---------                                          *
*  sean.kerns@sdrc.com                                     *
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