Answer: Echinococcus sp. protoscoleces
Each protoscolex has an internal row of hooklets that will evert one inside of the canine definitive host and become the head of the adult tapeworm.
A couple of readers asked me about the Carmine stain. It's unfortunately not one that we perform in the lab anymore although there are instructions and recipes in many major parasitology texts and online. It's really a beautiful way to highlight the structures of various worms, but just not something that we usually need for diagnostic purposes. I try to show photos of these 'older' stains from time to time to hopefully inspire others who want to revive them for teaching purposes.