Three hundred horse-soldiers were apportioned to each legion, divided into 10 troops (_turmae_), out of which three officers were chosen named Decuriones. The infantry furnished by the Socii was for the most part equal in number to the Roman legions, the cavalry twice or thrice as numerous, and the whole were divided equally between the two consular armies. Each Consul named 12 superior officers, who were termed Praefecti Sociorum, and corresponded by the Legionary Tribunes. _Fourth Period. From the times of the Gracchi until the downfall of the Republic._[50]--After the times of the Gracchi the following changes in military affairs may be noticed: In the first consulship of Marius the legions were thrown open to citizens of all grades, without distinction of fortune. The whole of the legionaries were armed and equipped in the same manner, all being now furnished with the pilum. The legionaries, when in battle-order, were no longer arranged in three lines, each consisting of ten maniples with an open space between each maniple, but in two lines, each consisting of five cohorts, with a space between each cohort. The younger soldiers were no longer placed in the front, but in reserve, the van being composed of veterans. As a necessary result of the above arrangements, the distinction between Hastati, Principes, and Triarii ceased to exist. The Velites disappeared. The skirmishers, included under the general term Levis Armatura, consisted for the most part of foreign mercenaries possessing peculiar skill in the use of some national weapon, such as the Balearic slingers, the Cretan archers (_sagittarii_), and the Moorish dartmen. When operations requiring great activity were undertaken, such as could not be performed by mere skirmishers, detachments of legionaries were lightly equipped, and marched without baggage for these special services.[51] The cavalry of the legion underwent a change in every respect analogous to that which took place with regard to the light-armed troops. The Roman Equites attached to the army were very few in number, and were chiefly employed as aids-de-camp and on confidential missions. The bulk of the cavalry consisted of foreigners, and hence we find the legions and the cavalry spoken of as completely distinct from each other. After the termination of the Social War, when most of the inhabitants of Italy became Roman citizens, the ancient distinction between the Legiones and the Socii disappeared, and all who had served as Socii became incorporated with the Legiones.