§ 13. Each legion had as its standard an eagle (aquila, Fig. I), usually of bronze or silver, on a wooden staff. This
c. III, 64.
Each cohort, also, had a standard of its own (signum, Fig. 2). The bearer of this was called signifer. Sometimes the legion for brevity was called aquila, and in like manner the cohort was denoted by signum. The signum was usually an animal—a sheep, for instance — on a staff. Of course it would differ for different cohorts, so that the men in the confusion of battle might know their proper place.
B. G. II, 25
H. 30. H. 18.
B. G. IV, 261
There was another
B. G. II, 201 C. III, 89. Dio Cassius Lib. 40.