Collembola

Collembola, one of the two orders of insects known as the Apterygogeneae, on account of the complete absence of wings, not only from the living forms, but probably also from all their ancestors. They are popularly known as "Spring-tails," as they are provided with a springing apparatus situated on the under side of the body and usually tucked up under the abdomen. The typical genus is known as Podura, and is common among dead and damp leaves, beside pools, etc.; in this form there are no internal breathing tubes or tracheae.