I agree with Debra here, especially as the bacteria in septic systems break down much of the material that goes into them. Using recycled septic safe toilet paper is important too.

I have read that landfills basically hold trash, and that little of it has the opportunity to biodegrade, eventhough the product is biodegradable, like paper, or bugs.

You could also put the bug/tissue into a compost pile.

I often find myself contemplating this dilemma as well. In my community we have centralized composting program, so the debate is easy for me - it goes in our "green bag" for the City to collect and compost.

As for the option of flushing, most waste water treatment plants operate using microbes in an activated sludge process, and follow up by composting the biosolids once the water has been processed out. From there, sometimes the composted biosolids are used as soil amendment, but it depends on what arrangements your local treatment plant has. Mine, for example, has issues with overly high heavy metal content, and therefore the biosolids can't be applied to fields. In my case, although the bulk is reduced and stabilized through the wastewater treatment process, the end product is still landfilled. (At least, it was a couple of years ago). If you are really curious, I'd suggest calling your local Public Works office and ask to be put in touch with your wastewater treatment plant. (Incidentally, they really don't like non-biodegradable things ending up in the finished biosolids, so flushing is never an option for something that won't break down.)

Thank you for the well-thought-out responses. I had forgotten to mention in my original question that part of my dilemma was whether it was worse to add the object to the landfill or to use extra water by flushing the object. (We live in an area where the water table is dropping.) It hadn't occurred to me until now that if I don't flush the object on its own, but instead just leave it in the toilet so it is flushed the next time the toilet is used, no extra water will be used.