Basal lobe: of culicid genitalia, see claspette.
Basal post-costal vein: in Agrioninae, one of the cubito-anal cross- veins.
Basal segment of clasp: see side piece.
Basal space: that area on the primaries of certain Lepidoptera, between the base and t. a. line (q.v.).
Basal streak: in Noctuid moths, extends from base, through the submedian interspace to the t. a. line.
Basal transverse carina: on the metanotum of Hymenoptera, crosses before middle and separates the anterior from the median areas.
Base: that part of any appendage that is nearest the body: on the thorax that portion nearest the abdomen; on the abdomen that portion nearest the thorax.
Basement membrane: that thin layer of tissue upon which the epithelium rests.
Basilar: of or pertaining to the base.
Basilar cross-vein: Odonata; crosses the basilar space.