A larva of such moth, which when walking alternate legs and prolegs, giving the appearance of measuring
Any of various caterpillars of the family Geometridae, who when walking alternate legs and prolegs, giving the appearance of measuring
One of numerous genera and species of moths, of the family Geometridæ; so called because their larvæ (called loopers, measuring worms, spanworms, and inchworms) creep in a looping manner, as if measuring