Two 1941 Japanese Katanas

I picked this up at an antique store today for a great price and I want to find out more about them. They both have the exact same markings but one is a couple inches shorter and has a different hilt design. The hilt design on one appears to be some type of flower while the other resembles a bird. I am most interested in finding out what the markings in the last photo mean. Any help is greatly appreciated.