Nicene and Post-Nicene Fathers, Ser. II, Vol. XIV:
The Canons of the Synods of Sardica, Carthage, Constantinople, and Carthage Under St. Cyprian, Which Canons Were Received by the Council in Trullo and Ratified by II. Nice.: Canon XIV

p. 449 Canon XIV.

That one of the bishops of Tripoli should come as legate, and that a presbyter might be heard there by five bishops.

It also seemed good that one bishop from Tripoli, on account of the poverty of the province, should come as a legation, and that there a presbyter might be heard by five bishops, and a deacon by three, as has been noted above, his own bishop presiding.

Notes.

Ancient Epitome of Canon XIV.

On account of the scarcity of bishops in Tripoli, one bishop shall suffice for a legation.

This canon is made up of two parts.  The first part is Canon v. of the synod of Hippo, a.d. 393, and was repeated at the Carthaginian synod of 397.  The second half is from Canon viij. of the same council.

Johnson (See Canon 12).

“Legate,” i.e., to a Synod, there being few bishops in that province.