The cavalry battalion was originally formed with 4 companies (McCash, p. 252). The units were as follows, Company A, the Richmond Hussars; Company B, the Fulton Dragoons; Company C, the Georgia Troopers; and, Company D, the Dougherty Hussars.
This number was later expanded to 11 (which would be Letter Companies
A-L), and then decreased to ten by the transfer of Company L to the
Phillips Legion. "...in addition a "spare" (11th) company in the Cobb
Legion Cavalry was moved over into the Phillips Legion Cavalry and was
lettered Company G and known as the "Richmond Dragoons"
(http://www.angelfire.com/tx/RandysTexas/page28.html). Sifakis, also
mentions this transfer.