The remaining ‘commissioned officers’, as we should call them, are represented by the troop and company commanders, the decurions who commanded the _turmae_ of the ala, and the centurions and decurions of the cohorts. The senior officer in each class was styled _decurio princeps_ or _centurio princeps_,[78] but apart from this we cannot trace any regular order of precedence with fixed titles such as is found among the legionary centurions. As regards the respective position of infantry and cavalry officers, the _decurio alae_ ranked highest. This is shown clearly, as von Domaszewski has pointed out, by the frequent employment of this officer as _praepositus cohortis_.[79] On the other hand, among the officers of the cohorts the centurions ranked above the decurions who commanded the mounted men, where such existed. In one inscription, which seems to have included all the officers of a _cohors equitata_, the centurions come first on the list, and in the Coptos inscription, so often cited, the officers of the 61 _equites cohortales_ are not mentioned at all.[80] The difference in rank cannot, however, have been very great since all these officers could be promoted to the post of legionary centurion without any intervening step, although this distinction seems to have been conferred most freely upon the decurions of the alae. In these cases it was of course necessary for the auxiliary officer to have acquired the _civitas_ either by serving his full time or by a special grant before his promotion. Throughout the period these posts seem usually to have been filled by promotion from the lower ranks, although we also find instances of legionaries being given commissioned rank in the auxiliary regiments, and it is officers of this class who seem most frequently to have secured further promotion to the legionary centurionate.[81] Von Domaszewski wishes to consider that these transfers were especially characteristic of the early days of the imperial army, and that a deliberate attempt was then made to provide every auxiliary regiment with a staff of ex-legionaries. With this suggestion, however, it is difficult to agree; not only is the epigraphical evidence insufficient to prove such a wholesale use of imported officers, but the cases known to us are by no means confined to the first fifty years of the Empire. Further, as will be shown later, the arrangement does not harmonize with the general character of the early _auxilia_.