Patrick --

Militia organizations were entirely different from volunteer or regular army units. For starters, regimental numbers represented men from specific counties, the case in question being the 72nd Militia Regiment from Russell County. That regiment had been in existence for many years, perhaps decades, but members could only be seen when they assembled for annual or biannual drills.

The Governor of Virginia could call state militia units into service -- active duty, if you prefer -- for limited terms. The 72nd Militia Regiment could have been called into service for ninety days or less at some point during 1861. The governor's papers or those of the state adjutant general would include orders to this effect.

It could be that the writer was talking about volunteer militia companies which organized in 1861. Militia regiments mentioned above were statutory and had existed for years. Volunteer companies organized under state laws for volunteer militia. These were accepted and officers commissioned by the governor upon receipt of proper muster rolls. The governor then directed companies to report to specific camps where they were organized into battalions and regiments. When properly organized the governor offered these organizations to the Secretary of War.

The writer may have been thinking about volunteers in these camps rather than statutory militia regiments like the 72nd of Russell County.