The Catalina 36's are sleaker and very pretty, while the Catalina 34's
are more squared off and boxy looking.

It's easy to tell them apart. You will think to yourself, that's a pretty
boat and then find out it's a C-36.

http://www.catalina36.org/Brochure90_1.jpg

http://www.c34.org/images/windy.gif

Bobsprit wrote

hanging on. The wind abated just as suddenly and we popped up. I looked to
port
and a Catalina 34 or 36 had her mainsail split.