Plexiglass is a brand name for acrylic. You can glue them together but you will need a cement designed for acrylic bonding. Weldon 3,4 or 16 will work, the 3 and 4 are water thin and have to be applied with an applicator (the 3 dries faster than the 4) and the 16 has a syrupy consistency. There is also a product called "plastic welder", I don't remember who makes it (maybe Devcon?) that would also work and probably be easier for you to find for this single project. You may be able to find the pthers locally, look in the yellow pages under plastics and see if you have any listings. Good luck, Skip