The Trajanic reliefs show several varieties of uniforms in addition to the ordinary type described above. The flying column which the emperor leads down the Danube includes men who wear, instead of the ordinary helmet, an animal’s skin arranged over the head and shoulders in the manner usually confined to standard-bearers, and others whose helmets are of a curious Teutonic pattern.[407] These may belong to regular cohorts which had been allowed to retain something of their national costume, but a barbarian who appears in this scene and elsewhere clad only in long loose breeches and a _sagum_, and whose chief weapon is a knotted club, must represent a _numerus_. Others of these irregular regiments are probably represented by the archers clad in long tunics and pointed caps or wearing helmet and shirt of scale armour who appear in one or two scenes.[408] They are certainly to be distinguished from the archers of the _cohortes sagittariorum_, who appear in a uniform which only differs from that of the ordinary auxiliary infantry in the absence of the shield.[409] The most exceptional uniform is that of the slingers, who are dressed simply in tunics with no armour but a shield.[410] Cichorius[411] wishes to recognize in them men from the Balearic Islands, but although the Baleares were employed by the Republic we have no inscriptions of a Cohors Balearum under the Empire. Moreover, if there existed cohorts of slingers with this distinctive uniform we should expect to find _cohortes funditorum_ or _libritorum_ on the analogy of the _cohortes sagittariorum_. It appears, on the contrary, from a passage in Hadrian’s speech to the African army that slinging formed part of the general training of all the auxilia.[412] Like the cavalry, the auxiliary infantry are represented on the Marcus column in a uniform essentially the same as that worn eighty years previously, and no further developments can be traced. The most striking fact which emerges from this inquiry is the general uniformity of the equipment of nine-tenths of the auxiliary regiments in the second century. We learn from casual references in Tacitus that this uniformity had always been the ideal of the Roman War Office,[413] and from the military point of view there was doubtless much to recommend it. It has, however, more significance if we regard it as one phase in that extension of a uniform material culture through at any rate the western half of the Empire which marks the first and second centuries. Footnotes: [374] Arrian, _Tactica_, 4 and 34-41. [375] The chronology of the Rhenish reliefs has been worked out by Weynand (_B. J. B._ 108/9), and the Danubian monuments have been similarly treated by Hofman (_Sonderschrift des Oesterreichischen Archäologischen Institutes in Wien_, Band v, 1905). [376] Figured by Lehner in the first part of his illustrated catalogue of the Bonn Museum, Plate vii, no. 3. [377] Figured by Cagnat, _L’Armée romaine d’Afrique_, p. 238. [378] Frontispiece.