Idiotype: a specimen named by the author after comparison with the type, but not also a topotype.
Ignitus: fire-red [vermilion].
Ileo-colon: the anterior portion of the hind-gut, extending from the mid-gut to the rectum, when not distinctly differentiated into ileum and colon.
Ileum: the small intestine; begins at end of chylific ventricle at the point where malpighian tubules join, and extends to colon.
Imaginal: pertaining to the adult or imago.
Imaginal buds, cells, or discs: in forms with a complete metamorphosis are those embryonic cells around and from which the organs and appendages of the future imago develop.
Imago: the adult or sexually developed insect.
Imbricate: arranged or appearing like the scales on a fish or the shingles on a roof.
Immaculate: destitute of spots or marks.
Immarginate: without an elevated rim or margin.