yeah, there is no third eye lid.. you can tell snake is sleeping if you an get them to sleep out in the open close to the glass ( not a easy task lol ) but if your snake will do this and I have seen mine do it, yiy c actually see that their actual pueple will slightly hang down Ward.. almost like they have lazy eyes.. lol
its pretty cute, but almost impossible to chatch them in the act! and as soon as you move to much infont of them their pueple shoots back up and you can tell that their awake.