Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules
The Parker used a similar lock tab as seen in your photo of the brass bodied revolver. With the absence of the "top-strap", the barrel assembly quickly slides forward, leaving the entire cylinder exposed, which is then removed and replaced with relative ease.
Reassembly is done by a few moves once the loaded cylinder is installed: align the barrel assembly on the center pin, slide into place and push the lock tab into position. Simple enough that it could be done on horseback by the Cavalrymen.
An observation here, also: having a brass bodied revolver without the "top strap" was never a good idea, as the brass lacks the necessary strength that steel has, especially in the larger calibers such as .44.
Here's my Fluted cylinder Parker assembled and then seen with the cylinder removed: