Dots/pods? gathering in circles on back glass

[LMDAVE]

Trying to figure out what these circle are on the glass. There was a small gathering on my front glass and about 3 on my back glass. I have a lot of brown algae on back glass, i thought these were bubbles at first, or maybe even pods, but not sure what tbe dots are why it’s gatbering in circles like this. Any ideas?

 

[Robink]

Do you have any snails? Could be snail eggs.

 

[LMDAVE]

Yes I do have several types of snails in the tank, so these could be snail eggs? They do kind of look like eggs. Interesting. Thanks.