Sicut Orberg nos docet, cum particium verbum sententiae est, desinentia casus ablativi utenda est -e. Si autem participium, adiectivum tantum est in sententia, desinentia casus ablativi -i utitur.
Num haec sententia recte composita?:
“Puella dormiens non ab ancilla canenti et ridenti, sed a servo clamante excitatur”(*)
Nonne rectius sit…
“Puella dormiens non ab ancilla canente et ridente, sed a servo clamante excitatur”?
Fortasse etiam…
“Puella dormiens non ab ancilla canenti et ridenti, sed a servo clamanti excitatur”
(*) Sic scriptam inveni in CD-ROM cui titulus est Exercitia Latina pars I.
Gratias plurimas Dii vobis dentur si me iuvare positis!
I think this “rule” is more of a tendency than a hard and fast rule. Although I haven’t done any sort of search, I’m sure you can find many instances in poetry where “violations” of this rule are confirmed by the meter (that is, short -e or long -i cannot be replaced by the alternative spelling because the meter would not allow a long vowel to replace a short vowel or vice versa).
Latin spelling was in a state of flux on many points during the classical period of the late Republic and early Principate. And the manuscripts on which our texts are based are very unreliable on details of spelling. For prose texts, which don’t have to conform to metrical constraints, in most cases there’s really no way to be absolutely sure what the author actually wrote from the evidence of the manuscripts.
Although ablative participles aren’t directly addressed, the appendix to the Oxford Classical Text edition of Ovid’s Metamorphoses (edited by Tarrant; p. 500) notes that igni is confirmed by the meter once and igne 13 times in the Metamorphoses; the figures given for Vergil are igni seven times, igne once. So Ovid and Vergil wrote both igni and igne in different proportions. That will give you an idea of the situation.
That said, you would expect consistency in a modern text prepared for educational purposes, especially where the “rule” is presented to the student.
As Qimmik said. As far as composition goes and writing Latin, I would stick to that rule, but be aware that in Latin authors it can go either way. I think it’s especially unstable in later Latin.
Any particular reason to explain option A as the one given in the CD-ROM answer key? Is there any difference in function between canenti/ridenti and clamante? If they are exactly the same then option B would be the most orthodox according to the rule, “nonne?”.
I’m at a loss on that one, all three are in identical constructions, so they should be treated the same way. I may be wrong, but I would say the participles are being used adjectivally here. The clearest example of the verbal use of a participle is the ablative absolute, which is generally where you will find the -e- ending.