One needs to be wary of the fact that indexs contain the names of all men recorded on muster rolls resulting in the recording of the same man under variant spellings. When you go to the actual CSRs, you will find that these variants are noted and reference one accepted spelling.

Note these found in the index for the 43rd Tennessee Infantry:

Avans, Westley, Co. H, Second Lieutenant, Private

Avens, Wesley, Co. H, Second Lieutenant, Private

Avons, Wesley, Co. H, Second Lieutenant, Private

Bishop, J. M., Co. H, Private, Sergeant

Bishop, James M., Co. H, Private, Sergeant

Carnes, William D., Co. C, Private, Fifer

Carnis, William D., Co. C, Private, Fifer

Costen, Z., Co. F, Private, Private

Costin, Z., Co. F, Private, Private

Coston, Zachariah, Co. F, Private, Private