A common name for Eisenia foetida and also Lumbricus rebellus. Eisenia foetida is a common worm used for vermicomposting, although in some parts of North America, Lumbricus rubellus is more common.
"Segments" are numerous disc-shaped portions of an earthworm's body bounded anteriorly and posteriorly by membranes. People identify earthworm species by counting the number of segments anterior to the position of structures such as the clitellum, ovaries, or testes. Segmentation is a characteristic of all annelids.
Soil is made up of mineral particles, organic matter, air, and water. The mineral particles are called sand, clay, or silt, depending on their size. Sand has large particles and feels gritty. Clay has fine particles and feels sticky or slippery when wet. Silt particles range between clay and very fine sand. Soil types have different amounts of each of these particles. Loam is a mixture of sandy soil, clay, and organic matter. The organic matter acts like a sponge to hold water.