"For the most part, it was just a matter of terminology. In the Western Theatre, most Confederate cavalry was really mounted infantry. The horses were a means of getting from one place to another."

While this is quite true to a large extent, it might be more accurate to say that Confederate mounted infantry and cavalry were used somewhat interchangeably in the Western Theatre [the actual troops, not the terms]. There are examples of cavalry fighting dismounted as infantry, and examples of mounted infantry charging and fighting on horseback.

Mounted infantry were brigaded with cavalry, but I don't know if they were also sometimes brigaded with infantry. I do seem to recall some examples of this...particular early and mid-war with Mississippi Mounted Infantry units.

It should also be noted that at least some of the Mississippi State Reserves, at least those near the end of the war, were not designated as cavalry, mounted infantry, or infantry...but they were on horseback. So perhaps this is indicative that the terms were losing their early war meaning.

"Most Confederate cavalry units carried a variety of weapons, which consisted of many 2-band or 3-band infantry rifles. Most common were .577 Enfields, .58 Springfields, .54 Austrians, and .69 smoothbore Springfields. Also carried were carbines of various types, and shotguns. As most fighting was done on foot, pistols were not widely carried."

As to weaponry, early in the war the shotguns were the preferred weapon for the cavalry. So much so that new recruits for the infantry were encouraged to bring their shotguns to enlistment, where they were exchanged for rifles and the shotguns were sent to the cavalry. These lost their appeal fairly early on, and the carbines became the weapon of choice. It would appear that the shotguns were then turned over to home defense units, as I have seen several examples where these units were requesting powder and shot for their shotguns during the mid-war period.

[Of course, these home defense shotguns may have been the shotguns that the men already had at home. However, contrary to our common beliefs, not many families owned weapons of any kind, according to early tax records. As another sidenote, most of the official Provost Guard units seem to have been equipped with flintlocks. At any rate, there seems to have been a pattern for weapons distribution in the South.]

I would have to say that the statement that "most fighting was done on foot" is overly broad, as that would be very, very difficult (if not impossible) to quantify.