Allen & Greenough p.364, Note 2: the dative plural "his" has a suffix "-ce" attatched:
"hisce omnis aditus ad Sullam intercludere"; (Cicero Pro Roscius Amerino 110.10) firstly, (A & G) have omitted some words, the full quote:
"hisce [aliqua fretus mora semper] omnis aditus ad Sullam intercludere" =
"[always relying on some delay], to shut these men from all access to Sulla (close to them [Latin: "his"] every approach)".
(The missing words are irrelevant to this Q., but I'm surprised that (A & G) would do this.)
I have looked at the readily-available Greek & Latin suffix charts, to no avail. Therefore, the significance of suffix "-ce" is, please?