Although this picture doesn’t give us a clear image of the organism, it shows us all we need to know in order to make an identification. We are confident that our reader’s initial suspicion was correct: this is a carpet beetle larva.

Among household pests, carpet beetle larvae are some of the most common and, unfortunately, destructive. They feed on a wide variety of items found in a household, which include animal products such as wool, feather, and felts (perhaps the hat is made out of one of these?) Since they have a nearly endless list of potential food sources, and the ability to survive for long periods of time without food, they can be rather tedious to get rid of. We recommend our reader start the process immediately. Since the larvae are in his hat, we advise that he either have the hat professionally cleaned or dispose of it immediately to limit the spread of these larvae. He should also investigate the area around the hat for signs of other larvae. Everything that has been disturbed should either be thrown out or professionally cleaned. Finally, he will need to start an intense daily cleaning regime to say goodbye to these larvae once and for all. The cleaning regime should include vacuuming, dusting, sweeping, and doing laundry every day until he is confident his home is carpet beetle larvae-free!

To summarize, a reader wrote to us about a brown worm-like organism that he noticed in his hat. The mysterious organism is a carpet beetle larva, which is what our reader thought it might be. Kudos to him on the detective work and best of luck getting rid of these obnoxious house guests!