That's happened to my gloves, too. It's caused by the sweat from your face. You're obviously training hard and keeping your hands up... good work.
Just clean the gloves with leather cleaner and rub some skin lotion on them, and they'll be fine.
To prevent the "chicken-skin effect" in the future, wipe down your gloves with a damp towel after each training session. That'll get the salt, etc off them.