multis nostrorum idcirco cadentibus, quod decernentes sub imperatoris conspectu, spe praemiorum, ut possint facile qui essent agnosci, nudantes galeis capita, sagittariorum hostilium peritia fundebantur.
Translation :
and many of our men fell for the reason that, fighting as they were under the emperor's eye, through the hope of rewards and wishing to be easily recognised they put off their helmets from their heads and so fell victims to the skill of the enemy's archers.
Edition :
Ammianus Marcellinus. With An English Translation. John C. Rolfe, Ph.D., Litt.D. Cambridge. Cambridge, Mass., Harvard University Press; London, William Heinemann, Ltd. 1935-1940.
