Sow bugs and pill bugs are the only two crustaceans that have adapted themselves entirely to land. They actually have gills instead of a trachea with which they breath. Sow bugs are related to snails and slugs. Sow bugs are virtually the same as pill bugs but have a wider body and cannot roll themselves into a ball and have two appendages that protrude from the rear of the body. They have oval bodies which have 7 overlapping plates, as well as 7 pairs of legs. Head and abdomen are small compared to rest of body and they can reach 3/4 inch in length. Pill bugs are often called rolly poly as they can roll up into a tight ball.
Both are scavengers which feed on decaying organic matter and can injure young plants. They like moist locations and are found under objects on the damp ground, as well as under vegetable debris of all kind. They may bury themselves several inches into the soil. They are active mostly at night.
The female carries her young in a pale colored vivarium or marsupium on the underside of her body. The young are white in color.