Chalcedony. A silicious mineral, like Cornelian.
Chalybeate. Water holding iron in solution.
Chara, Characidæ. An aquatic plant fossilized.
Cheirolepis (Thorny scale). A fossil fish.
Chelonia. Sea tortoise.
Chert. A silicious mineral, resembling common flint, but of coarser texture.
Chœropotamus. An extinct quadruped found in the Eocene of England.
Cheiracanthus (thorny hand). A fish of the Old Red Sandstone.
Cirrhipeda (hair feet). Balanus-Coronula; Anatifa are of this family.
Clinometer. An instrument for measuring the dip and determining the strike of beds or strata.