Bulla: a blister or blister-like structure: the shield-like sclerite that closes the opening to the trachea in lamellicorn larvae: in Ephemerida a part of the costal area of the fore wing toward the tip, which is slightly swollen forward and furnished with more cross veins than elsewhere; practically the stigma, q.v.

Bullate: blistered.

Bullule: a small blister.

Bursa: a pouch or sac: a wing pouch in male caddice flies and in connection with a stalked hair pencil.

Bursa copulatrix: the copulatory pouch of the female in some orders; a modification of the vagina.

[C]

Caducous-us: deciduous; easily detached or shed.

Caecal tubes or pouches: sac, or blind tube-like structures surrounding the chylific ventricle at its junction with the crop, and secreting a digestive ferment.

Caecum: a blind sac or tube-like structure serving as one of the caecal tubes or pouches: see coecum.

Caelate: a surface with plane elevations of varying forms.