Ravenna is in a region (Emilia-Romagna) where the operator didn't share its timetables with the rest of the world. Also, regional trains from 12 June have just been published on the Trenitalia website and will take some time to get to other planners. Except "of course” for Emilia-Romagna. Please use the Trenitalia website to plan Italian journeys. Reservations for day trains in Italy can best be made via ÖBB using these steps (no booking fees, as opposed to booking via Eurail).

Thank you for this info. I already purchased Eurail passes as I also needed Zurich rails. Should I cancel my Eurail passes or is it possible to still book these seats through Eurail when they post to Eurails website?

I'm not sure what you mean here. What kind of Eurail passes have you bought exactly? And what do you mean by "I also needed Zurich rails”?

Sorry, let me clarify. I bought a Eurail Global pass because I will be using the rail in Switzerland and in Italy. I thought this was the best route to go since using the rail in multiple countries. I am VERY new to this and this is a first for me. 

Your global passes are perfectly valid in Switzerland and Italy and many other countries.

What @rvdborgt means is that with your Eurail Pass on some trains you need a reservation, this reservation you can get also on other websites like tickets.oebb.at and not only via Eurail.com(+booking fee). Also he means, that you have to look for the timetable on trenitalia.com.

And-to add a little more confusion-in most countires (except mostly ESpana) some, local/regional trains do NOT need any REServation-in fact it cannot even be done. IF you use those trains, you only need to register trip and show conductor that, if s/he even comes along, Its perfectly possible to go that way from Fi to Ra-change Bologna. It will take a little longer and the trains may be less luxurious, but millions of Europeans use that every day-for work/school/trips etc.

In some countires these trains are the norm, like in Swiss, Nederland, Belgium, Denmark-they go so often (at least ev hour) that planning and REServation and all that hassle is superfluous.

Do NOT use app of pass to plan- a site like bahn.de (=german trains) has more info is far more uptodate and will clearly show if a train MUST be REServed-or not.

Thank you all. So I can safely assume that trains from Florence to Ravenna on July 18 and Ravenna to Rome on July 28 just have not been added into Eurail’s system yet. They SHOULD eventually have this route, correct?

Yes, they should, and elsewhere too. But what's in Eurail's system is not that important. Italian timetables are best checked on www.trenitalia.com and reservations for day trains are best done via ÖBB (after the trains have become available).