Strange object on back glass

[Apheoxx]

Strange object on back glass, anyone have a clue as to what it is?

 

[EeyoreIsMySpiritAnimal]

Snail eggs. Do you have nassarius snails?

 

[ISpeakForTheSeas]

I agree, these are snail eggs - if you don't have Nassarius snails, some Ceriths lay eggs that can look like this too (though this pattern isn't as common amongst Ceriths).

 

[Nick Steele]

My ceriths lay eggs like that all the time!