Earthworm: Ext. Morphology & Reproduction (55x90cm)

An “Earthworm: External Morphology & Reproduction” (55×90 cm) educational chart presents clear, colored diagrams of the earthworm’s segmented body, key external features, and detailed notes on its reproductive systems and process, supporting zoology teaching and laboratory reference.​

External Morphology

Body Plan and Segmentation: The earthworm is long, cylindrical, bilaterally symmetrical, and divided into 100–120 rings or segments (somites). The dorsal surface has a visible dark blood vessel; the ventral side features genital openings and papillae.​

Key Features:

Mouth and Prostomium: Crescent-shaped mouth at the anterior end, just below a lobe called the prostomium, which assists in digging.​

Clitellum: A prominent thickened glandular ring encircling segments 14–16 in mature worms, critical for reproduction and cocoon formation.​

Setae: S-shaped bristles in each segment (except the first, last, and clitellum) for locomotion; diagram often shows arrangement and structure.​

Apertures: Mouth (1st segment), anus (last segment), spermathecal pores (segments 5/6 to 8/9), male genital pores (18th segment), and female genital pore (14th segment).​

Reproductive System & Process

Hermaphroditism: Each earthworm has both male and female reproductive organs (bisexual).​

Male System: Testes (segments 10–11), vasa deferentia, accessory glands, prostate gland, and male pores (18th segment).​

Female System: Ovaries, oviducts, and female genital pore (14th segment).​

Spermathecae: Pairs of storage sacs (segments 6–9) for receiving sperm during mating.​

Reproductive Process:

Earthworms reproduce sexually via cross-fertilization. During copulation, two worms align ventrally, exchange sperm, and store it in spermathecae.​

Clitellum secretes a mucus cocoon; eggs, stored and received sperm, and nutritive fluid are deposited and the cocoon slips off, where fertilization occurs externally. Direct development leads to young hatchlings.​

This chart is ideal for visualizing anatomy, identifying reproductive and external features, and explaining earthworm biology in school or undergraduate study.