Callosity: a thick swollen lump, harder than its surroundings: = callous: also a rather flattened elevation not necessarily harder than the surrounding tissue.
Callous: see callosity.
Callus: a small callosity.
Caltrops spines: the branched and otherwise specialized irritating spines in Limacodid larvae.
Calva: a skull-cap: = epicranium, q.v.
Calx: the distal end of the tibia; the curving basal portion of the first tarsal joint.
Calyculate: applied to antennae, whose cup-shaped joints are so arranged as to fit one into the other.
Calypter: Diptera; the alula or squama when it covers the haltere.
Calyptra: a hood or cap; see alula.
Calyptrate: those flies that have aluke or membranous scales above the halteres.