5. L.CalpurniusPisoCaesoninus, L. F. C. N., son of No. 4, was consul B. C. 112 with M. Livius Drusus. In B. C. 107 he served as legatus to the consul, L. Cassius Longinus, who was sent into Gaul to oppose the Cimbri and their allies, and he fell together with the consul in the battle, in which the Roman army was utterly defeated by the Tigurini in the territory of the Allobroges. [LONGINUS, No. 5.] This Piso was the grandfather of Caesar's father-in-law, a circumstance to which Caesar himself alludes in recording his own victory over the Tigurini at a later time. (Caes. Gal. 1.7, 12; Oros. 5.15.)