Hooray! I found two more mushrooms - golden mushroom and skinny mushroom - and Granny made a beautiful mushroom soup.
This was a frustratingly tedious game, beautifully written, but oh so many things to examine. It seems that you have to examine some things in a certain order. In the case of the grass, I had examined it several times and then, out of the blue, I examined it again and found the item that I desperately needed. There's no logic to this. Now I have to go back and find out what I did or what I examined that triggered the successful examination of the grass.
In at least two locations, examining something will reveal multiple things and you have to examine all of those things to find a hidden mushroom, as the mushroom is hidden at random. You might not notice this unless you play the game several times and take careful notes.
I haven't found the sequence in the cave with the extra graphic, so I'll have to go back and look for that. Was it related to the ceiling? I was careful not to poke around with that, as I didn't want it collapsing on me.
Now, on to the next game . . .