bulla

bulla (noun; plural bullae; Latin bulla, bubble): 1. A rounded prominance, blister- or knob-like.

2. (Arthropoda: Crustacea) A structure secreted by the head and maxillary glands of certain parasitic female copepods that serves as an anchor for attachment to gill filaments of fish.

3. (Arthropoda: Insecta) a. Weakened spots on concave wings that allows them to bend

See also: stigma. b. In diaspid Hemiptera, located in the terminal outlet of wax glands (ceratuba) at the inner end. c. In scarabaeoid Coleoptera, a sclerite that closes the trachea. 4. (NEMATA: Secernentea) In Heteroderidae, knoblike structures within the vulval cone of cysts near the underbridge or fenestra.