This was accompanied by severe social stresses and the greater collapse of the middle classes. As a result, the Roman state was forced to arm its soldiers at the expense of the state, which it did not have to do in the past. The distinction between the heavy infantry types began to blur, perhaps because the state was now assuming the responsibility of providing standard-issue equipment. In addition, the shortage of available manpower led to a greater burden being placed upon Rome's allies for the provision of allied troops. Eventually, the Romans were forced to begin hiring mercenaries to fight alongside the legions. Legion after the reforms of Gaius Marius In a process known as the Marian reforms, Roman consul Gaius Marius carried out a programme of reform of the Roman military. In 107, all citizens, regardless of their wealth or social class, were made eligible for entry into the Roman army. This move formalised and concluded a gradual process that had been growing for centuries, of removing property requirements for military service. The distinction among the three heavy infantry classes, which had already become blurred, had collapsed into a single class of heavy legionary infantry. The heavy infantry legionaries were drawn from citizen stock, while non-citizens came to dominate the ranks of the light infantry. The army's higher-level officers and commanders were still drawn exclusively from the Roman aristocracy. Unlike earlier in the Republic, legionaries were no longer fighting on a seasonal basis to protect their land. Instead, they received standard pay, and were employed by the state on a fixed-term basis. As a consequence, military duty began to appeal most to the poorest sections of society, to whom a salaried pay was attractive. A destabilising consequence of this development was that the proletariat "acquired a stronger and more elevated position" within the state. The legions of the late Republic were almost entirely heavy infantry. The main legionary sub-unit was a cohort of approximately 480 infantrymen, further divided into six centuries of 80 men each. Each century comprised 10 "tent groups" of 8 men. Cavalry were used as scouts and dispatch riders, rather than as battlefield forces. Legions also contained a dedicated group of artillery crew of perhaps 60 men. Each legion was normally partnered with an approximately equal number of allied (non-Roman) troops. The army's most obvious deficiency lay in its shortage of cavalry, especially heavy cavalry. Particularly