The Katydid's name comes from the sound it makes. Also called Bush Cricket and Long-Horned Grasshopper, there are over 6,400 species. They range in size from a little less than one-quarter inch to almost five inches. Sharing the same order (orthopetera) with grasshoppers, they have much longer and thinner antennae. Also related to the cricket, they both make their sound by rubbing their wings together. Grasshoppers rub their legs together. The Katydid sound, which is specific to each species, can be heard by the other species. They communicate important messages about such things as mating and territory. Their sound is also temperature related, which can be calculated with considerable accuracy by applying a formula to the number of vibrations per second.