All three of these are in .45 caliber. But only the 1911 is associated with the caliber. The Anaconda is more commonly associated with .44 Magnum and a Glock is more commonly thought of as a 9mm.
Which made me think to take this picture:
All three of these guns aren't in the caliber originally developed for them. The Pocket Hammerless is in .380 ACP rather than .32 ACP. The Government Model is in .38 Super rather than .45 ACP. The Anaconda is in .45 Colt rather than .44 Magnum. The Glock 21 is in .45 ACP rather than 10mm ACP.