From the "Four Seasons" mosaic. The mosaic, inv. 1018, is from Harbiye, from the second century A.D. It's named after the winged figures representing the seasons. This is a detail of "A pig hunt in Calydonia", which is situated between Spring and Summer. The man in the middle seems to be Meleager, to his left Atlanta (the catalogue probably means "Artemis" in view of the story, the Enc. Britt. mentions Atalanta as "a parallel and less important form of the goddess Artemis").
From the Enc. Britt. we understand this was not just any boar hunt: (Meleager:) in Greek mythology, the leader of the Calydonian boar hunt. The Iliad relates how Meleager's father, King Oeneus (q.v.) of Calydon, had omitted to sacrifice to Artemis, who sent a wild boar to ravage the country. Meleager collected a band of heroes to drive it away and eventually killed it himself. The Calydonians and the Curetes (neighbouring warriors who aided in the hunt) then quarrelled over the spoils, and war broke out between them. At one point the Curetes besieged Calydon and were ready to take it when Meleager finally repulsed them.