=Armilustrium=, a festival at Rome on the 19th of October. When the sacrifices were offered, all the people appeared under arms. The festival has often been confounded with that of the Salii, though easily distinguished; because the latter was observed the 2nd of March, and on the celebration of the Armilustrium they always played on a flute, and the Salii played upon the trumpet. It was instituted A.U.C. 543. _Varro_, _de Lingua Latina_, bk. 5, ch. 3.――_Livy_, bk. 27, ch. 37. =Arminius=, a warlike general of the Germans, who supported a bloody war against Rome for some time, and was at last conquered by Germanicus in two great battles. He was poisoned by one of his friends, A.D. 19, in the 37th year of his age. _Dio Cassius_, bk. 56.――_Tacitus_, _Annals_, bk. 1, &c. =Armorĭcæ=, cities of Celtic Gaul, famous for the warlike, rebellious, and inconstant disposition of the inhabitants called Armorici. Armorica extended between the rivers Liger and Sequana, and comprehended those rich and populous provinces now called Britany and Normandy. _Cæsar_, _Gallic War_. =Arne=, a city of Lycia, called afterwards Xanthus.――――A town of Umbria in Italy.――――A daughter of Æolus, who gave her name to two towns, one in Thessaly, the other in Bœotia. Neptune changed himself into a bull to enjoy her company. _Strabo_, bks. 1 & 2.――_Pausanias_, bk. 9, ch. 40.――_Ovid_, _Metamorphoses_, bk. 6, fable 4. =Arni=, a people of Italy, destroyed by Hercules. =Arniensis=, a tribe in Rome. _Livy_, bk. 6. =Arnobius=, a philosopher in Diocletian’s reign, who became a convert to christianity. He applied for ordination, but was refused by the bishops till he gave them a proof of his sincerity. Upon this he wrote his celebrated treatise, in which he exposed the absurdity of irreligion, and ridiculed the heathen gods. Opinions are various concerning the purity of his style, though all agree in praise of his extensive erudition. The book that he wrote, _De Rhetoricâ Institutione_, is not extant. The best edition of his treatise _Adversus Gentes_ is the 4to, printed Leiden, 1651. =Arnus=, a river of Etruria, rising in the Apennine mountains, and falling into the Mediterranean. _Livy_, bk. 22, ch. 2. =Aroa=, a town of Achaia. _Pausanias_, bk. 7. =Aroma=, a town of Caria,――――of Cappadocia. =Arpāni=, a people of Italy. =Arpi=, a city of Apulia, built by Diomedes after the Trojan war. _Justin_, bk. 20, ch. 1.――_Virgil_, _Æneid_, bk. 10, li. 28. =Arpīnum=, a town of the Volsci, famous for giving birth to Cicero and Marius. The words _Arpinæ chartæ_ are sometimes applied to Cicero’s works. _Martial_, bk. 10, ltr. 19.――_Juvenal_, satire 8, li. 237. ――_Cicero_, _De Lege Agraria contra Rullum_, speech 3.――――A town of Magna Græcia. =Arræi=, a people of Thrace. _Pliny._ =Arrharæus=, the king of a nation in the neighbourhood of Macedonia, who greatly distressed Archelaus. _Aristotle_, bk. 5, _Politics_, ch. 10.