third declension accusative plural

[Aenesidemus]

At Suet. Calig. 9 we have

Apud quos quantum praeterea per hanc nutrimentorum consuetudinem amore et gratia valuerit, maxime cognitum est, cum post excessum Augusti tumultuantis et in furorem usque praecipites solus haud dubie ex conspectu suo flexit


"tumultuantis ...praecipites " bothers me. Are they both accusative plural? if they are, why would Suetonius use different endings in the same sentence? Does the -is ending seem more appropriate to him with a present participle?

 

[cinefactus]

Interesting. Just looking on phi, one of the first hits is
transiit in Asiam auxiliisque contractis et praefecto regis prouincia expulso nutantis ac dubias ciuitates retinuit in fide.

Most of the hits are on participles, although there are some nouns as well:
Studium et fides erga clientis ne iuueni quidem defuerunt.
Prisco rege inter minores gentis adlecta in senatum

 

[Aenesidemus]

Interesting. Just looking on phi, one of the first hits is
transiit in Asiam auxiliisque contractis et praefecto regis prouincia expulso nutantis ac dubias ciuitates retinuit in fide.

Most of the hits are on participles, although there are some nouns as well:
Studium et fides erga clientis ne iuueni quidem defuerunt.
Prisco rege inter minores gentis adlecta in senatum

Thanks for your response. in the third quote you offer, we have the same problem, don't we? why two different endings in two adjacent words, minores and gentis?

 

[Avunculus H]

Historically, -īs is the ending of the Indo-European i-stem class, -ēs of the IE consonant stem class, which to a big degree were merged in Latin; -ēs is the ending that generally won out, while - īs is an archaism that stuck in specific words, comparable to how some English words have "irregular" plurals like oxen or mice. gens is one of these old i-stems (the nom. sg. was *g'n.h1tis in Proto.Indo-European, the i was lost due to apocope in the prehistory of Latin.) Sometimes - īs was also wrongly applied to words that aren't old i-stems (comparable to how people wrongly construct forms like I *doth or he *doest when trying to write archaizing English), like the participles. These things are irregular and so depend on what forms a specific writer saw as the correct form.