Hey Forty Rod....very observant ! ! ! I was wondering the same thing and I found a website that tends to make you think the .36 Dance pistol had the round trigger guard and the .44 Dance pistol have the squareback trigger guard....
here is the website.....Look at the 6th photo under the Dance catagory
http://civilwarhandgun.com/obscure.htm they show a pice of a dance with a squareback trigger guard....
I have been looking all over a Dance pistol and noticed that one of the sellers were listing them as " Second Generation"
.......anybody else see that

It seems that the photo you are refering to is the photo of a replica, not an original one. If you look closely at the tagg for the gun with theTexas star on, it's labelled .44. Thedetails of the gun on the 6th photo are very like on the replica including the CH frame.