Plutarch Crassus 28

[1] During the night the Parthians, although they were aware of the flight of the Romans, did not pursue; but as soon as day came, they attacked and slaughtered those who had been left behind in the Roman camp, to the number of four thousand, and then rode about and seized many who were wandering in the plain.

[2] Four cohorts together, also, which Vargontinus the legate had suffered to get detached from the main body while it was still dark, and which had lost their way, were surrounded on a sort of hill, and cut to pieces as they fought, all except twenty men. The Parthians, admiring these men, who tried to push their way through them with drawn swords, made way for them and suffered them to pass through and march deliberately to Carrhae. A false report now reached Surena that Crassus, along with, the men of highest rank, had made his escape, and that the fugitives who had streamed into Carrhae were a mixed rabble unworthy of his notice.

[3] Supposing, therefore, that he had lost the fruits of his victory, but being still in doubt and wishing to learn the truth, in order that he might either wait there and lay siege to Crassus in the city, or else let Carrhae alone and pursue him, he sent one of his attendants who could speak both languages up to the walls, with orders to call out in the Roman tongue for Crassus himself or Cassius, saying that Surena wished to have a conference with them.

[4] The interpreter gave this message, and when it was reported to Crassus, he accepted the invitation. A little while afterwards there came from the Barbarians some Arabs, who knew Crassus and Cassius well by sight, having been in their camp before the battle. When these men saw Cassius on the wall, they said that Surena proposed a truce, and offered them safe conduct if they would be friends of the king and leave Mesopotamia; for this he saw was more advantageous to both parties than any resort to extreme measures.

[5] Cassius accepted the proposal, and asked that time and place be fixed for a conference between Surena and Crassus. The men said that this should be done, and rode away.