Lower Sonoran faunal area: comprises the most arid deserts of North America, beginning west of lat. 98 degrees in Texas: sends narrow arms into southern New Mexico, is interrupted by the Continental Divide; covers a large part of w. and s. Ariz., s. w. Nev., s. w. Calif., a portion of central Calif., and most of Lower Calif. These areas are irregular and incapable of brief definition. Lubricate -ous: covered with a slippery mucus. Lucid: shining; applied to luminous insects. Luciferase: a substance in the nature of an enzyme, existing in the luminous organs of light-giving beetles. Luciferine: a substance in the blood of luminous beetles which, when brought into contact with luciferase, produces light. Luciferous: light giving. Lucifugous: fleeing the light: applied to nocturnal forms or those that live in concealment. Lumen: the cavity of an organ: the inner surface of a tube: the hollow portion of a gland or vesicular structure. Luminescence: applied to the light of fire-flies, as a substitute for phosphorescence. Lumper: one who, in describing species or genera recognizes only prominent or obvious characters to the exclusion of minor color or variable characters of maculation or structure: see splitter. Lunaris or Lunate: crescent-shaped: formed like a new moon. Lunula: a small lunule or crescent. Lunulae: in Hymenoptera, crescent-shaped marks near the orbits. Lunulate: a line, when made up of a series of small lunules. Lunule: a lunate mark or crescent. Lurid -us: dirty brown with a bluish tinge [pale brown + a little French blue]: also used to indicate an obscuring of bright colors. Luteo -testaceous: dark clay yellow. Luteous -eus: clay yellow [pale clay yellow]. Lutescent: becoming or appearing to be clay yellow. Lutose -us: apparently or really covered with dirt. Lymphatic: producing, carrying or relating to the lymph. Lyrate: lyre-shaped: cut into several transverse segments, and gradually enlarging towards the extremity. Lyre: the upper wall or border of the spinning tube of caterpillars. M Macrochaetae: the long bristles occurring singly on the body of Diptera. Macropterous: long or large winged. Macrosomites: the primitive regions of primitive hand of the insect embryo. Macula: a colored mark larger than a spot; of indeterminate figure. Maculate -ed: spotted or marked with figures of any shape, of a color different from the ground. Maculation: the ornamentation or pattern of marking. Maculose: spotted; with many marks or spots. Maerianum: "that segment of the post-pectus situate one on each side behind the acetabulum and parapleurum"; it supports the posterior feet: see meriaeum. Magenta: pinkish red; an aniline product. Magis: more. Maggot: applied to the footless larvae of Diptera. Mala: a lobe: a ridged or grinding surface. Mala mandibularis: the grinding surface or area of a mandible.