Fish, Snail, and Poodle Novelty Pins, Fahrner, ca 1930s-1950s

These are three fun sterling silver and marcasite novelty pins. The first is a fish which is quite long, nicely stylized, and adorned with silver filigree and marcasites. It is marked on the back Germany, Sterling, S. Christian, but does not include Fahrner's circle TF mark like similar ones on the web. The second one is snail, similarly equipped with silver filigree and marcasites. It has copper-colored guilding on parts of its impressive shell, and a small chain with safety pin anchored to the pin's back. It is marked Original Fahrner and also has the circle TF mark. The last pin is a black enamel poodle with sweet curlycues; marcasites in the head, ear, and collar; and a small red glass eye. This one is missing the circle TF mark, but we have another nearly identical one that does have it.

Enjoy and all comments are welcome! Does anyone know the purpose of the snail's chain and safety pin?