new 'stuff' in my tank

I've got a small tank with just one male betta and a snail in it.

Just now, I noticed a few spots of what looks like little silver balls in a
stringy (looks kind of sticky) clear substance. The silver balls almost look
like mercury balls -they're that shiny and silver.

What the heck is that stuff? There's a tiny bit sticking to the side of the
blass and then a larger bunh floating upwards from a leaf...

Any ideas?

TIA,
Mary