A few years ago, a somewhat extended thread on Latin pronunciation (I believe the main controbutors were WYSISWYG, Dicho, Q, Joe- went into this subject.

1. Don is essentially correct. The Latin of the Romans is lost. Church Latin evolved, Italians and many RC clergy using a modified Italian pronunciation. Anglican (old school) again differs somewhat.
Example- Agnus Dei is pronunced An-yus Day-e in RC, and most Anglican, service, but scientific Latin, especially Botanical Latin, differs- Ag-nus Day-e generally accepted in English where extended Latin is required, e. g., descriptions of new plant species, where a Latin diagnosis is necessary.

A few comments from William T. Stearns on pronunciation:
Scientific Latin was based on Erasmus, 1528, De recta Latini Graecique Sermonis Pronunciatione.
He described speeches to Emperor Maxmilian; the French ambassador with a Gallic accent, a German speaking as if he was speaking German, a Dane who spoke like a Scotchman, etc.

Stearn- "In English-speaking countries there exist two main systems, the traditional English pronunciation generally used by gardeners and botanists and the "reformed" or "restored" academic pronunciation adopted by classical scholars as presenting "a reasonably close approximation to the actual sounds of the language as spoken by educated Romans"."
"This academic pronunciation comes closer to the usual Latin pronunciation of Continental People than does the conventional English pronunciation.
"Words containing more than one vowel or diphthong (i. e. two vowels pronounced as one, e. g. ae, au, ei, eu, oe, ui) are divided into syllables." Thus al-bus, mag-nus, ple-nus, etc., ple-ni-flo-rus, etc.
In Latin, every vowel is pronounced, hence co-to-ne-as-ter...and in endings -o-i-des (not oi-des).
"In classical Latin words of several syllables the stress falls on the syllable next to the last one (penultimate) when this syllable is long...e. g. for-mo'-sus....but falls on the last syllable but two ...when the last one is short, e. g. flo'-ri-dus, sil-va'ti-cus.
....the 'i' sound varies, as eye in al-pi'-nus but te in se-ro-ti-nus; the short i in words of Greek origin. .
Consonents as in English.

Table later. A lot of stuff here.