The Horseshoe Crab - Limulus polyphemus - Promotes public awareness of the four remaining species. Natural history, conservation, medical uses, education, sightings, stories, images, glossary, and bibliography.
Horseshoe Crabs: The Ancient Mariner - Information on these crabs, which have evolved little in the last 250 million years, their behavior and mating ritual.
Limulus polyphemus - Exercise from Invertebrate Anatomy OnLine covering the systematics, natural history, external and internal anatomy and trilobite larva of this horseshoe crab.
Merostomata - Brief description of the class, from the Animal Diversity Web.
