Q: Limit to rotating desktop pictures?

Hello,  I recently created an album of wallpaper that I wanted to have rotating on one of the desktops for my Macbook Pro.  I started manually adding them in small groups at a time and I always let them go through to make sure they looked good on the desktop.  After a while though, I noticed that when it was rotating it would only go through a portion of them instead of all of the pictures so I'm not sure if I changed a setting by accident or if there is a number limit for how many can rotate.  I counted at one point that it was rotating between the first 108 photos which seemed like an odd number for a limit. Thanks for any help.