Are these egg sacs or something else?

[Joe Rice]

When I returned from a two week vacation I noticed these on the scraper I had left in the tank. They kind of look like egg sacs to me but of what, I have no notion. Any ideas? Interesting that two appear reddish and the others are clear.

 

[Coastie Reefer]

Have any nerite snails?

 

[Tahoe61]

^ Yup.

 

[Joe Rice]

Yes, I do. Hopefully now I have a few more than I used to

Thanks!