Reglazing 1902 Wood Sash

Have vinyl clad windows and on the face near the bottom are two oval holes that are 3/8x1-1/4, some have rubbers plugs with a small square hold, not sure the purpose but some are missing allowing for bees to get in. Anyone know where one can get the plug or whatever it is called?

Hello everyone, I live in a house with a pretty decent sun room addition. It's aging though and the screens on the outside of the sliding windows are getting old. Because of that, they cannot withstand my dog jumping through them when he gets excited. :P For the life of me, I cannot figure out how to take the screen frames out to replace the material. I've looked both inside and out and the frames don't appear to be removable. I've taken the 2 sliding glass windows out of the slides but there is no frame for the screen to move at all. The screws around the window can be removed, but all of the sun room frame appears to be holding itself together and no one piece can be easily removed. Is it possible that you're supposed to replace the screens while they sit there upright? Seems pretty awkward. Provided some pictures here: [url]https://imgur.com/a/Ny6nW74[/url] Thanks for the help!