[121] iii. 11213 gives the sequence _eques-optio-decurio_, and 8762 that of _eques-vexillarius-decurio_, but such details are rare. [122] The _principales_ would be the _vexillarius alae_, the _optio singularium_, and a _duplicarius_ and _sesquiplicarius_ to each _turma_. Of the _immunes_ each _turma_ has its _signifer_, _custos armorum_, and _curator_. The total number of the _beneficiarii_, &c., we do not know, but the inscription of the Equites Singulares quoted above suggests an average of three to a _turma_. In a _cohors quingenaria_ with only 6 commissioned officers and 19 _principales_ (the _imaginifer cohortis_ and the _signifer_, _optio_, and _tesserarius_ of each century) the chances of promotion would be less. This is another reason for the popularity of the cavalry and the desire of cohorts to become _equitata_. Cf. Tac. _Hist._ iv. 19. [123] The Ala Indiana may have been called after the Trevir Iulius Indus mentioned in Tac. _Ann._ i. 42, the Ala Siliana after C. Silius the general of Tiberius, and the Ala Pannoniorum Tampiana after Tampius Flavianus, governor of Pannonia in 69. The last case, however, is doubted by von Domaszewski, _Rangordnung_, p. 122, n. 6. [124] The only cases known at present are the cohorts Lepidiana and Apuleia civium Romanorum, and a Cohors Flaviana only known from a _cursus honorum_. [125] The name of the tribe was usually in the genitive plural but might also be in the nominative singular. Thus we find the same regiment described as Cohors I Alpinorum and Cohors I Alpina. The question of duplicate numbering, which is connected with the system of recruiting and distribution, is discussed in the following section. [126] The fact that the numerous regiments bearing this title appear in the diplomata shows that the status of their members was not permanently raised. One regiment, the Cohors II Tungrorum, bears the title C(ivium) L(atinorum), _Eph. Ep._ ix. 1228. [127] Ritterling has shown that all the auxilia of Germania Inferior received the titles _pia fidelis Domitiana_ in 89 for their loyalty at the time of the rebellion of Saturninus; _W. D. Z._ 1893. The title _fida_ was borne by the Cohors I Vardullorum; vii. 1043. [128] It is borne by regiments of Dacians and Britons who cannot have acquired it during the reign of Augustus; D. xxxix, iii. 10255. [129] vii. 818, 819, 820 and 823. [130] As in the case of the legions this title was probably borne by regiments which had been formed by a combination of two previously existing units. The two Alae Flaviae Geminae, for example, which appear in Germania Superior at the end of the first century, would represent the salvage of the old Rhine army which went to pieces in 69. [131] The alae Britannica, Gaetulorum, Gallorum, Parthorum, and I Thracum, and the Cohorts I Aquitanorum, III Brittonum, I Hispanorum, I Sugambrorum, and III Thracum. [132] _Rangordnung_, p. 80.