Canadia spinosa is a fossil annelid or “ringed worm” about 1 to 2 inches in length. The head bore a pair of slender tentacles while the body was covered with innumerable setae or short bristles. Canadia used its limbs to both walk and swim. Sediment has never been found in the gut, suggesting that this worm may have been a carnivore or scavenger. Canadia are some of the most photogenic of the Burgess Shale fossils.
Hallucigenia sparsa from the Burgess Shale (Royal Ontario Museum 61513), 15 mm long. Hallucigenia was originally interpreted upside-down, with its spikes in the sediment and its appendages collecting and passing food towards its large, bulbous head. Image credit: Jean-Bernard Caron.
Hallucigenia: a Burgess Shale fossil. The Burgess Shale Formation in the Canadian Rockies of British Columbia, is one of the world's most famous fossil fields. At 505 million years (Middle Cambrian) old, it is one of the earliest fossil beds containing exceptionally well preserved soft-part fossils.