University of California
Ucmp: The Ophiuroidea
All about the Ophiuroidea. Includes a picture of the fossil along with the history.
Other
Wet Web Media: Spiny Skinned Animals & Echinodermata
Site provides a general overview of echinoderms from the perspective of the marine aquarium enthusiast. Content includes a focus on physical characteristics, individual classes, and acquarium maintenance.
California Academy of Sciences
California Academy of Sciences: Echinoderm Webpage
Resource provides a brief overview of echinoderms. Includes pictures and links for more information.
Other
Hawaii Coral Reef Network: Ophiuroidea, Brittle Stars
This page simply contains a picture of a spiny brittle star. A good example of this echinoderm.