When alive, Pikaia was a compressed, leaf-shaped animal.
It swam by throwing its body into a series of S-shaped, zigzag curves, similar to the movement of eels.
Fish inherited the same swimming movement, but they generally have stiffer backbones.
Pikaia had a pair of large head tentacles and a series of short appendages, which may be linked to gill slits, on either side of its head.

Middle Cambrian
Burgess Shale, Stephens Formation
Field, British Columbia, Canada
Excellent injection-molded CAST of 1.6 inch animal on 2.4 inch slab
Problematica, Burgess Shale.

Casts are affordable visual aids to fossil collectors, museum curators, and science teachers.  They are life-size copies of actual fossils which complement any fossil display or reference collection.  This cast is especially well-made, even replicating the somewhat reflective quality of the actual fossil and the color of the actual matrix.